View source for Attachment theory

{{Short description|Psychological ethological theory}}
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[[File:Eskimo Family NGM-v31-p564-2.jpg|upright=1.4|thumb|right|alt=An Inuit family is sitting on a log outside their tent. The parents, wearing warm clothing made of animal skins, are engaged in domestic tasks. Between them sits a toddler, also in skin clothes, staring at the camera. On the mother's back is a baby in a papoose.|For infants and toddlers, the "set-goal" of the hypothesized behavioural system is to maintain or achieve proximity to attachment figures, usually the parents.]]

'''Attachment theory''' posits that infants need to form a close relationship with at least one primary caregiver to ensure their survival, and to develop healthy social and emotional functioning.<ref>{{cite encyclopedia |year=1999 |title=The Nature of a Child's Ties |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York |url=https://archive.org/details/handbookofattach0000unse/page/3 |pages=[https://archive.org/details/handbookofattach0000unse/page/3 3–20] |isbn=1-57230-087-6 |veditors=Cassidy J, Shaver PR |vauthors=Cassidy J}}</ref><ref name="Abrams Turner Baumann Karel 2013 pp. 149–155">{{cite book |last1=Abrams |first1=David B. |title=Encyclopedia of Behavioral Medicine |last2=Turner |first2=J. Rick |last3=Baumann |first3=Linda C. |last4=Karel |first4=Alyssa |last5=Collins |first5=Susan E. |last6=Witkiewitz |first6=Katie |last7=Fulmer |first7=Terry |last8=Tanenbaum |first8=Molly L. |last9=Commissariat |first9=Persis |publisher=Springer New York |year=2013 |isbn=978-1-4419-1004-2 |publication-place=New York, NY |pages=149–155 |chapter=Attachment Theory |doi=10.1007/978-1-4419-1005-9_939 |quote=Bowlby (1969, 1988) described an attachment as an emotional bond that is characterized by the tendency to seek out and maintain proximity to a specific attachment figure, particularly during times of distress. |last10=Kupperman |first10=Elyse |last11=Baek |first11=Rachel N. |last12=Gonzalez |first12=Jeffrey S. |last13=Brandt |first13=Nicole |last14=Flurie |first14=Rachel |last15=Heaney |first15=Jennifer |last16=Kline |first16=Christopher |last17=Carroll |first17=Linda |last18=Upton |first18=Jane |last19=Buchain |first19=Patrícia Cardoso |last20=Vizzotto |first20=Adriana Dias Barbosa |last21=Martini de Oliveira |first21=Alexandra |last22=Ferraz Alves |first22=Tania C. T. |last23=Cordeiro |first23=Quirino |last24=Cohen |first24=Lorenzo |last25=Garcia |first25=M. Kay |last26=Marcano-Reik |first26=Amy Jo |last27=Ye |first27=Siqin |last28=Gidron |first28=Yori |last29=Gellman |first29=Marc D. |last30=Howren |first30=M. Bryant |last31=Harlapur |first31=Manjunath |last32=Shimbo |first32=Daichi |last33=Ohta |first33=Keisuke |last34=Yahagi |first34=Naoya |last35=Franzmann |first35=Elizabeth |last36=Singh |first36=Abanish |last37=Baumann |first37=Linda C. |last38=Karel |first38=Alyssa |last39=Johnson |first39=Debra |last40=Clarke |first40=Benjamin L. |last41=Johnson |first41=Debra |last42=Millstein |first42=Rachel |last43=Niven |first43=Karen |last44=Niven |first44=Karen |last45=Miles |first45=Eleanor |last46=Turner |first46=J. 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Rick |last102=Pulgaron |first102=Elizabeth R. |last103=Wile |first103=Diana |last104=Baumann |first104=Linda C. |last105=Karel |first105=Alyssa |last106=Schroeder |first106=Beth |last107=Davis |first107=Mary C. |last108=Zautra |first108=Alex |last109=Stark |first109=Shannon L. |last110=Whang |first110=William |last111=Soto |first111=Ana Victoria |last112=Gidron |first112=Yori |last113=Wheeler |first113=Anthony J. |last114=DeBerard |first114=Scott |last115=Allen |first115=Josh |last116=Mitani |first116=Akihisa |last117=Mitani |first117=Akihisa |last118=Pulgaron |first118=Elizabeth R. |last119=Mitani |first119=Akihisa |last120=Carter |first120=Jennifer |last121=Whang |first121=William |last122=Schroeder |first122=Beth |last123=Hicks |first123=Angela M. |last124=Korbel |first124=Carolyn |last125=Baldwin |first125=Austin S. |last126=Spink |first126=Kevin S. |last127=Nickel |first127=Darren |last128=Richter |first128=Michael |last129=Wright |first129=Rex A. |last130=Thayer |first130=Julian F. |last131=Richter |first131=Michael |last132=Wright |first132=Rex A. |last133=Wiebe |first133=Deborah J.}}</ref> It was first developed by psychiatrist and psychoanalyst [[John Bowlby]] (1907–90).<ref name="Brimhall Haralson 2017 pp. 1–3">{{cite book |last1=Brimhall |first1=Andrew S. |last2=Haralson |first2=David M. |title=Encyclopedia of Couple and Family Therapy |chapter=Bonds in Couple and Family Therapy |publisher=Springer International Publishing |publication-place=Cham |year=2017 |isbn=978-3-319-15877-8 |doi=10.1007/978-3-319-15877-8_513-1 |pages=1–3 |quote=Bond is an emotional attachment between one or more individuals. To be considered an attachment bond, the relationship must have four defining characteristics: proximity maintenance, separation distress, safe haven, and secure base.}}</ref> The theory proposes that secure attachments are formed when caregivers are sensitive and responsive in [[social interaction]]s, and consistently available, particularly between the ages of six months and two years. As children grow, they are thought to use these attachment figures as a ''secure base'' from which to explore the world and to return to for comfort. Interactions with caregivers have been hypothesized to form a specific kind of ''attachment behavioral system'' – or, more recently, ''internal working model'' – the relative in/security of which influences characteristic patterns of behavior when forming future relationships.<ref name="Bretherton/Mul">{{cite encyclopedia |year=1999 |title=Internal Working Models in Attachment Relationships: A Construct Revisited |encyclopedia=Handbook of Attachment:Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York | veditors = Cassidy J, Shaver PR |pages=[https://archive.org/details/handbookofattach0000unse/page/89 89–114] |isbn=1-57230-087-6 |author=Bretherton I, Munholland KA |url=https://archive.org/details/handbookofattach0000unse/page/89 }}</ref> Separation anxiety or grief following the loss of an attachment figure was proposed as being a normal and adaptive response for a securely attached infant.{{sfn|Prior|Glaser|2006|p=17}}

In the 1970s, [[Developmental psychology|developmental psychologist]] [[Mary Ainsworth]] expanded on Bowlby's work, codifying the caregiver's side of the attachment process as necessitating the adult's availability, appropriate responsiveness and sensitivity to infant signals. She and her team devised a laboratory procedure known as the [[Strange Situation |Strange Situation Procedure]], which she used to identify attachment patterns in infant-caregiver pairs: secure; avoidant; anxious attachments; and later, disorganized attachment.<ref>{{Cite journal |last1=Bernard |first1=Kristin |last2=Meade |first2=Eb |last3=Dozier |first3=Mary |date=November 2013 |title=Parental synchrony and nurturance as targets in an attachment based intervention: building upon Mary Ainsworth's insights about mother–infant interaction |journal=Attachment & Human Development |language=en |volume=15 |issue=5–6 |pages=507–523 |doi=10.1080/14616734.2013.820920 |pmc=3855268 |pmid=24299132}}</ref><ref name="Bretherton">{{cite journal | vauthors = Bretherton I |year=1992 |title=The Origins of Attachment Theory: John Bowlby and Mary Ainsworth | url = https://archive.org/details/sim_developmental-psychology_1992-09_28_5/page/759 |journal=Developmental Psychology |volume=28 |issue=5 |pages=759–775 |doi=10.1037/0012-1649.28.5.759}}</ref> In the 1980s, attachment theory was extended to adult relationships and [[attachment in adults]], making it applicable beyond early childhood.<ref name="Hazan, Shaver, 1987">{{cite journal | vauthors = Hazan C, Shaver P | title = Romantic love conceptualized as an attachment process | url = https://archive.org/details/sim_journal-of-personality-and-social-psychology_1987-03_52_3/page/511 | journal = Journal of Personality and Social Psychology | volume = 52 | issue = 3 | pages = 511–24 | date = March 1987 | pmid = 3572722 | doi = 10.1037/0022-3514.52.3.511 }}</ref> Bowlby's theory integrated concepts from [[evolutionary biology]], [[object relations theory]], [[Control theory |control systems theory]], [[ethology]], and [[cognitive psychology]], and was most fully articulated in his trilogy, ''Attachment and Loss'' (1969–82).<ref name="simpson">{{cite encyclopedia |year=1999 |title=Attachment Theory in Modern Evolutionary Perspective |encyclopedia=Handbook of Attachment:Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York |veditors = Cassidy J, Shaver PR |pages=[https://archive.org/details/handbookofattach0000unse/page/115 115–40] |isbn=1-57230-087-6 |author=Simpson JA |url=https://archive.org/details/handbookofattach0000unse/page/115 }}</ref>

While criticized from its inception by academic psychologists, ethnographers and psychoanalysts in the 1950s,<ref name="Rutter 95" /> attachment theory has become a dominant approach to understanding early social development and has generated extensive research.<ref name="Schaffer">{{cite book |title=Introducing Child Psychology | vauthors = Schaffer R |publisher=Blackwell |year=2007 |isbn=978-0-631-21628-5 |location=Oxford |pages=83–121}}</ref> Several researchers–notably [[Michael Lamb (psychologist)|Michael Lamb]] and his colleagues in the mid-1980s–have shown that the diagnoses of attachment security or insecurity constructed using procedures like the [[Strange Situation]] are primarily reflections of what was going on in the social environment during the procedure, external to the child and his or her caregiver(s).<ref>{{cite journal |last1=Lamb |first1=Michael E. |last2=Thompson |first2=Ross A. |last3=Gardner |first3=William P. |last4=Charnov |first4=Eric L. |last5=Estes |first5=David |title=Security of infantile attachment as assessed in the 'strange situation': Its study and biological interpretation |journal=Behavioral and Brain Sciences |date=March 1984 |volume=7 |issue=1 |pages=127–147 |doi=10.1017/S0140525X00026522 }}</ref><ref>{{cite book  | vauthors = Lamb M, Thompson R, Gardner W, Charnov E, Cannon J | editor-first1 = Michael E. | editor-first2 = Ross A. | editor-first3 = William | editor-first4 = Eric L. | editor-last1 = Lamb | editor-last2 = Thompson | editor-last3 = Gardner | editor-last4 = Charnov | title = Infant–Mother Attachment: The Origins and Developmental Significance of Individual Differences in Strange Situation Behaviour |publisher=Erlbaum |place=Hillsdale NJ | year = 1985 | doi = 10.4324/9780203781791 | isbn = 978-1-134-92918-4 }}{{pn|date=November 2025}}</ref> Other findings challenge the theory's observational claims, its claims to universal cultural relevance, the role of temperament in shaping attachment behaviour, the unobservability of internal working models, and the limitations of discrete attachment patterns. Such criticisms are rarely addressed by attachment advocates<ref>{{cite book |title=The Myth of Attachment Theory: A Critical Understanding for Multicultural Societies |publisher=Routledge |location=London |year=2021 |isbn= 978-1-00-316709-9 |author-last1=Keller |author-first1=Heidi  }}{{pn|date=November 2025}}</ref> and so the theory's core concepts continue to influence therapeutic practices and social and childcare policies. Recent findings show that attachment theory is mistaken to assume a one-to-one program underpins infant social behaviour. In short, attachment theory overemphasizes maternal influence on shaping children's social lives while overlooking [[Gene|genetic]], cross-cultural, and broader social factors.<ref name=":1">{{cite journal |last1=Picardi |first1=Angelo |last2=Fagnani |first2=Corrado |last3=Nisticò |first3=Lorenza |last4=Stazi |first4=Maria Antonietta |title=A Twin Study of Attachment Style in Young Adults: A Twin Study of Adult Attachment Style |journal=Journal of Personality |date=October 2011 |volume=79 |issue=5 |pages=965–992 |doi=10.1111/j.1467-6494.2010.00707.x |pmid=21204839 }}</ref><ref name=":3">{{cite thesis |last1=Benware |first1=Jared P. |title=Predictors of Father-Child and Mother-Child Attachment in Two-Parent Families |date=2013 |doi=10.26076/e6fd-dae1 |doi-access=free }}</ref><ref name=":10">{{cite web |last1=Barbaro |first1=Nicole |title=Rethinking the Transmission Gap: What Behavioral Genetics and Evolutionary Psychology Mean for Attachment Theory |url=http://toddkshackelford.com/downloads/Barbaro-et-al-PsychBull.pdf |publisher=Psychological Bulletin}}</ref><ref name="keller">{{cite journal |vauthors=Keller H |date=November 2018 |title=Universality claim of attachment theory: Children's socioemotional development across cultures |journal=[[Proceedings of the National Academy of Sciences of the United States of America]] |volume=115 |issue=45 |pages=11414–11419 |bibcode=2018PNAS..11511414K |doi=10.1073/pnas.1720325115 |pmc=6233114 |pmid=30397121 |doi-access=free}}</ref>

==Attachment==
[[Image:Mozambique024.jpg|thumb|alt=A young mother smiles up at the camera. On her back is her baby gazing at the camera with an expression of lively interest.|right|Although it is usual for the mother to be the primary attachment figure in some Westernized cultures, infants will form attachments to any carer who is sensitive and responsive in social interactions with them.]]

Within attachment theory, ''attachment'' refers to an [[affectional bond]] or tie between an individual and an attachment figure, usually a caregiver or guardian. Such bonds may be reciprocal between two adults, but between a child and a caregiver, the bonds arise mainly from the child's own actions in pursuit of safety, security, and protection—which is most important in infancy and childhood.<ref>{{cite journal |last1=Murphy |first1=Anne |last2=Steele |first2=Miriam |last3=Dube |first3=Shanta Rishi |last4=Bate |first4=Jordan |last5=Bonuck |first5=Karen |last6=Meissner |first6=Paul |last7=Goldman |first7=Hannah |last8=Steele |first8=Howard |title=Adverse Childhood Experiences (ACEs) Questionnaire and Adult Attachment Interview (AAI): Implications for parent child relationships |journal=Child Abuse & Neglect |date=February 2014 |volume=38 |issue=2 |pages=224–233 |doi=10.1016/j.chiabu.2013.09.004 |pmid=24670331 }}</ref> Attachment theory is not an exhaustive explanation of human relationships. For example, Ainsworth speculated that attachment was a "synonym of love,"<ref>{{cite journal |last1=Ainsworth |first1=Mary D. Salter |title=Object Relations, Dependency, and Attachment: A Theoretical Review of the Infant-Mother Relationship |journal=Child Development |date=1969 |volume=40 |issue=4 |pages=969–1025 |doi=10.2307/1127008 |pmid=5360395 |jstor=1127008 }}</ref> though not all of a baby's relationships are love relationships. 

In child-to-adult relationships, the child's tie is called the "attachment" and the caregiver's reciprocal equivalent is referred to as the "caregiving bond".<ref name=pg15>[[#PriorGlaser06|Prior and Glaser]] p. 15.</ref> Just as the child's tie is generated through the operation of a hypothesized "attachment behavioral system" (ABS) in the child, so the caregiving bond is held to be produced by the caregiver's "caregiving behavioral system."<ref>{{cite book | vauthors = Cassidy J | chapter = The Nature of a Child's Ties. | veditors = Cassidy J, Shaver PR | title = Handbook of attachment: Theory, research, and clinical applications. | url = https://archive.org/details/handbookofattach0000unse_n9k8 | edition = 2nd | location = New York, NY | publisher = Guilford Press | date = 2008 | pages = [https://archive.org/details/handbookofattach0000unse_n9k8/page/41–105 }}</ref> The theory proposes that children attach to carers instinctively,<ref name="BrethQuote">{{cite news|author=Bretherton I|title=The Origins of Attachment Theory: John Bowlby and Mary Ainsworth|year=1992|quote=[Bowlby] began by noting that organisms at different levels of the phylogenetic scale regulate instinctive behaviour in distinct ways, ranging from primitive reflex-like "fixed action patterns" to complex plan hierarchies with subgoals and strong learning components. In the most complex organisms, instinctive behaviours may be "goal-corrected" with continual on-course adjustments (such as a bird of prey adjusting its flight to the movements of the prey). The concept of cybernetically controlled behavioural systems organized as plan hierarchies (Miller, Galanter, and Pribram, 1960) thus came to replace Freud's concept of drive and instinct. Such systems regulate behaviours in ways that need not be rigidly innate, but – depending on the organism – can adapt in greater or lesser degrees to changes in environmental circumstances, provided that these do not deviate too much from the organism's environment of evolutionary adaptedness. Such flexible organisms pay a price, however, because adaptable behavioural systems can more easily be subverted from their optimal path of development. For humans, Bowlby speculates, the environment of evolutionary adaptedness probably resembles that of present-day hunter-gatherer societies. However, he did not find ethnographic data to back his views as hunter-gatherers breed cooperatively, ''not'' in isolated nuclear families with a home-alone mother.}}</ref> making the biological aim of attachment survival and its psychological aim security.<ref name="Schaffer"/> 

The relationship that a child has with their attachment figure is deemed to be especially important in threatening situations, particularly if there are no other caregivers around as is often the case in nuclear families with a traditional division of labour. The presence of at least one supportive attachment figure is especially important in a child's developmental years.<ref>{{cite journal |last1=Stupica |first1=Brandi |last2=Brett |first2=Bonnie E. |last3=Woodhouse |first3=Susan S. |last4=Cassidy |first4=Jude |title=Attachment Security Priming Decreases Children's Physiological Response to Threat |journal=Child Development |date=July 2019 |volume=90 |issue=4 |pages=1254–1271 |doi=10.1111/cdev.13009 |pmid=29266177 }}</ref> In addition to support, attunement (accurate understanding and emotional connection) is crucial in a caregiver-child relationship. If the primary caregiver and the child are poorly attuned, the child may grow to feel misunderstood and anxious.<ref>{{Cite web |date=2023-04-04 |title=Attunement |url=https://www.evolveinnature.com/blog/2023/3/7-attunement-the-real-language-of-love |access-date=2023-08-23 |website=Evolve In Nature |language=en-US}}</ref>

Attachment theory holds that infants may form attachments to ''any'' consistent and available caregiver who is sensitive and responsive in social interactions with them. The quality of social engagement is more influential than the amount of time spent. In a [[nuclear family]] with traditional female-male roles, the biological mother is the usual principal attachment figure, but the role can be assumed by anyone who consistently behaves in a "mothering" way over a period of time. Within attachment theory, mothering equates to a set of behaviours that involves engaging in lively social interaction with the infant and responding readily to signals and approaches.<ref>Bowlby (1969) p. 365.</ref> Nothing in the theory suggests that fathers are not equally likely to become principal attachment figures if they provide most of the child care and related social interaction.<ref>[[#Holmes93|Holmes]] p. 69.</ref><ref>{{Cite news|last=Cosentino|first=Ashley|date=5 September 2017|title=Viewing fathers as attachment figures|url=https://ct.counseling.org/2017/09/viewing-fathers-attachment-f%E2%80%8A%E2%80%8A%E2%80%8Aigures/|url-status=live|website=Counseling today|archive-url=https://web.archive.org/web/20170924022707/http://ct.counseling.org:80/2017/09/viewing-fathers-attachment-f%E2%80%8A%E2%80%8A%E2%80%8Aigures/ |archive-date=2017-09-24 }}</ref> A secure attachment to a father who is a "secondary attachment figure" may counter the possible negative effects of an unsatisfactory attachment to a mother who is the primary attachment figure.<ref>{{Cite journal |last1=Lamb |first1=Michael E. |last2=Lamb |first2=Jamie E. |date=1976 |title=The Nature and Importance of the Father-Infant Relationship |journal=The Family Coordinator |volume=25 |issue=4 |pages=379–385 |doi=10.2307/582850 |jstor=582850 }}</ref>

"Alarm" is the term used for activation of the ABS caused by fear of danger. "Anxiety" is the anticipation or fear of being cut off from the attachment figure. And, if an attachment-figure is unavailable or unresponsive, separation distress may occur.<ref name="pg16">[[#PriorGlaser06|Prior and Glaser]] p. 16.</ref> In infants, extended physical separation can lead to anxiety and anger, followed by sadness and despair. The theory holds that, after the ABS has fully-formed (by age three or four), extended physical separation is no longer such a threat to the child's bond with the attachment figure. Threats to security in older children and adults arise from prolonged absence, breakdowns in communication, emotional unavailability or signs of rejection or abandonment.<ref name=kobmad/>

===Tenets===
Modern attachment theory is based on three principles:<ref name=":9">{{cite book |title=Attachment Theory in Practice: Emotionally Focused Therapy (EFT) with Individuals, Couples and Families |last=Johnson |first=Susan M. |publisher=The Guildford Press |year=2019 |isbn=978-1-4625-3828-7 |location=New York |page=5}}</ref>  
# One-to-one bonding is an intrinsic human need. 
# The regulation of emotion and fear can enhance vitality.
# The promotion of adaptiveness and growth. 

====Primate beginnings====
While Bowlby believed attachment behaviour was a product of human evolution and, in evidence, proposed that infant primates also manifested attachments, he did not make a distinction between primates who breed cooperatively—happily passing newborns from adult to adult like marmosets and tamarins—and primates who jealously rear their young one-to-one, as do gorillas and chimpanzees.<ref>{{cite book |title=Mothers and Others: The Evolutionary Origins of Mutual Understanding |url=https://archive.org/details/mothersothersevo0000hrdy |last=Hrdy |first=Sarah Blaffer |publisher=The Belknap Press of Harvard University Press |year=2009 |isbn=978-0-674-03299-6 |location=United States of America}}</ref> So he proposed that one-to-one ''attachment behaviours'' and their associated emotions were likely to be [[Adaption|adaptive]] in the young of ''all'' primates who socialised in the possessive one-to-one manner of gorillas and chimps, a group which he (mistakenly) believed to include human hunter-gatherers and therefore, our [[Stone Age]] ancestors. 

It is a truism that the long-term evolution of any social species must have involved selection for social behaviours—in both infants ''and'' adults—that make individual or group survival more likely in that species. Yet, distinctively, Bowlby's theory did ''not'' focus on how much the survival of primate infants depended on the caring behaviour of their older companions. His theory's primary focus attributed infant survival to something innate in newborns themselves. This meant his theory initially sidelined the advantages for infant safety of adult vigilance and caregiving, focusing instead on toddlers' own efforts to stay near familiar people when they feel stressed. This emphasis made him suggest that the crucial factor for infant safety and survival, both today and in the environment of pre-human adaptation, must have been the acquisition and development of an innate 'attachment system' which now underpins the panhuman social psychology of infancy.

====Hunter-gatherers====
While citing no ethnographic evidence, Bowlby pictured the evolutionary environment of early pre-human adaptation as one in which, like gorillas and chimpanzees, the infant was always in close proximity to their mother, being "carried by his mother on her back", a picture which he (incorrectly) assumed also to represent current [[hunter-gatherer]] societies.{{sfn|Bowlby|1971|p=300}} In sidelining the efficacy of protective caregiving initiatives from the infant's older companions, that is ''the caregiving behavioural system'', he was led to propose that there would be a survival necessity for infants to evolve the capacity to sense possibly dangerous conditions such as isolation from companions or rapid approach by strangers. Hence, according to Bowlby, evolution must have ensured that young children's proximity-seeking to a ''mother-figure'' in the face of threat has become the "set-goal" of what he called the attachment ''instinct'' or ''attachment behavioural system''.<ref>{{Cite book|last=Bowlby|first=John|url=https://mindsplain.com/wp-content/uploads/2020/08/ATTACHMENT_AND_LOSS_VOLUME_I_ATTACHMENT.pdf|title=Attachment and loss|publisher=[[Basic Books]]|year=1969–1982|page=11|language=English}}</ref>

====Monotropy====
Reflecting his own experience and his observations of English families, Bowlby believed the one-to-oneness of the child's first strong relationship  was a human universal, using the term "monotropy" to describe it.<ref>Bowlby (1969)</ref> Attachments form most obviously if the infant lives in social conditions which mean he or she has only one caregiver, with, perhaps, some occasional care from a small number of other people. Around the world, from the start of life onwards, most children have many more than one important figure in their lives with whom they may smile, cry, cling and play, or to whom (in Bowlby's [[psychobabble|language]]) they may 'direct attachment behaviour'. As within hunter-gatherer tribes, babies born into [[extended families]] are often raised cooperatively—a possibility Bowlby apparently did not consider. So, researchers and theorists have abandoned the concept of monotropy insofar as it may be taken to mean the relationship with the special figure differs ''qualitatively'' from that of other figures. Instead, current attachment theorists postulate very young children develop ''hierarchies'' of relationship.<ref name="Rutter 95">{{cite journal | vauthors = Rutter M | title = Clinical implications of attachment concepts: retrospect and prospect | url = https://archive.org/details/sim_journal-of-child-psychology-and-psychiatry-and-allied-disciplines_1995-05_36_4/page/549 | journal = Journal of Child Psychology and Psychiatry, and Allied Disciplines | volume = 36 | issue = 4 | pages = 549–71 | date = May 1995 | pmid = 7650083 | doi = 10.1111/j.1469-7610.1995.tb02314.x }}</ref><ref name="Main">{{cite encyclopedia |year=1999 |title=Epilogue: Attachment Theory: Eighteen Points with Suggestions for Future Studies |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York |url= https://archive.org/details/handbookofattach0000unse/page/845 |pages=[https://archive.org/details/handbookofattach0000unse/page/845 845–87] |isbn=978-1-57230-087-3 |quote=although there is general agreement an infant or adult will have only a few attachment figures at most, many attachment theorists and researchers believe infants form 'attachment hierarchies' in which some figures are primary, others secondary, and so on. This position can be presented in a stronger form, in which a particular figure is believed continually to take top place ("monotropy")&nbsp;... questions surrounding monotropy and attachment hierarchies remain unsettled |author=Main M |veditors=Cassidy J, Shaver PR}}</ref>

====From observable behaviour to internal cognitions====
As empirical research has eroded direct observational support—both for the universal existence of [[fixed action pattern| attachment behaviours]] and for stranger fear and separation anxiety—in human infants, the theory has come to emphasize the importance of early experiences with caregivers as giving rise to an ''internal'' system of thoughts, memories, beliefs, expectations, emotions, and behaviours about the self and others. This system, called by attachment advocates the "internal working model of social relationships", is hypothesized to continue to develop with time and experience.{{sfn|Mercer|2006|pp=39–40}}

While these ''internal working models'' still lack any agreed definition,<ref name="Thompson 2017">{{cite book |title= The Cultural Nature of Attachment: Contextualizing Relationships and Development |last1=Thompson |first1=Ross |publisher=MIT Press |location=Cambridge MA |year=2017 |isbn=978-0-262-03690-0 |editor-last1= Keller |editor-first1=Heidi |editor-last2=Bard |editor-first2=Kim |pages=303–304 |chapter=Twenty-First Century Attachment Theory: Challenges and Opportunities }}</ref> attachment theory now holds that they regulate, interpret, and predict attachment-related behaviour in the self and in the attachment figure. Supposing they develop in line with environmental and developmental changes, they would then incorporate the capacity to reflect and communicate about past and future attachment relationships.<ref name="Bretherton/Mul"/> As such, they would enable the growing child to handle new types of social interactions; knowing, for example, an infant should be treated differently from an older child, or that interactions with teachers and parents share characteristics. Internal working models are hypothesized to continue to develop through adulthood, helping cope with friendships, marriage, and parenthood, all of which involve different behaviours and feelings.<ref name="Bowlby 73">{{cite book |title=Separation: Anger and Anxiety | vauthors = Bowlby J |publisher=Hogarth |year=1973 |isbn=978-0-7126-6621-3 |series=Attachment and loss. Vol. 2 |location=London}}</ref>{{sfn|Mercer|2006|pp=39–40}} For example, one article has found that athletes' who have strong  relationships with their coaches thrive more than those who do not, especially if their needs are met. Some see this finding as a confirmation of attachment theory and the importance of internal working models.<ref>{{cite journal |last1=Davis |first1=Louise |last2=Brown |first2=Daniel J. |last3=Arnold |first3=Rachel |last4=Gustafsson |first4=Henrik |title=Thriving Through Relationships in Sport: The Role of the Parent–Athlete and Coach–Athlete Attachment Relationship |journal=Frontiers in Psychology |date=2 August 2021 |volume=12 |article-number=694599 |doi=10.3389/fpsyg.2021.694599 |pmc=8366224 |pmid=34408711 |doi-access=free }}</ref>

====Changes with age====
[[File:Kaitlyn reads a book..jpg|thumb|right|alt=A baby leans at a table staring at a picture book with intense concentration.| Insecure attachment patterns can compromise exploration and the achievement of self-confidence. A securely attached baby is free to concentrate on their environment.]]

Bowlby held that over the first three years human babies develop a feedback system (like a thermostat) which has proximity-to-mother or mother-figure as its "set-goal." Formation of this system has four phases. 

The raw materials for this system, first ''emitted'' (as Bowlby put it)<ref>Bowlby (1969) 2nd ed. pp. 244ff.</ref> over the two or three months after birth (which he called Phase One of attachment formation), Bowlby called "attachment behaviours": rooting, sucking, smiling, crying, reaching, clinging and looking. Even six-month-olds typically direct smiles, cries, and other attachment or ''proximity seeking'' behaviours indiscriminately towards caregivers, if more than one is available. Eventually, a single figure will become the focus of these behaviours, according to the theory. 

Where there is more than one caregiver, attachments to different caregivers are hypothesised to be arranged hierarchically, with the principal attachment figure at the top.<ref>Bowlby (1969) 2nd ed. pp. 304–05.</ref> The set-goal of the ABS is to maintain a bond with an accessible and available attachment figure.<ref name=kobmad>{{cite encyclopedia|author= Kobak R, Madsen S|year=2008|title= Disruption in Attachment Bonds|encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications| veditors = Cassidy J, Shaver PR | publisher= Guilford Press|location= New York and London|pages=23–47|isbn=978-1-59385-874-2}}</ref> 

During the second phase of attachment-formation (three to six months), the infant is said to ''start'' the process of discriminating between familiar and unfamiliar adults, beginning to become more selectively focused on the person who will ultimately become their preferred ''mother-figure''. 

Phase Three of attachment formation is said to last from around six or seven months of age to two or more years. Soon following and clinging are added to the range of proximity-seeking behaviours. This is the start of the infant's behaviour toward the caregiver becoming organized on a ''goal-directed'' basis to achieve the conditions that make it feel secure.{{sfn|Prior|Glaser|2006|p=19}} By the end of the first year, the infant will be able to display a range of attachment behaviours designed to maintain proximity. These manifest as protesting the caregiver's departure, greeting the caregiver's return, clinging when frightened, and following when able.{{sfn|Karen|1998|pp=90–92}}

With the development of locomotion, the infant is expected to begin to use the caregiver or caregivers as a "safe base" from which to explore.{{sfn|Prior|Glaser|2006|p=19}}<ref>{{cite book |title=Disorders of Childhood: Development and Psychopathology | first1 = Robin Hornik | last1 = Parritz | first2 = Michael F | last2 = Troy |date=2017 |isbn=978-1-337-09811-3 |edition=Third |publisher= Cengage Learning |location=Boston, MA |oclc=960031712}}{{pn|date=November 2025}}</ref> Infant exploration is expected to be greater when the caregiver is present because the infant's attachment system will be relaxed, making it freer to explore. If the caregiver is inaccessible or unresponsive, attachment behaviour should be more strongly exhibited.<ref name="ainsworth 67">{{cite book |title=Infancy in Uganda: Infant Care and the Growth of Love | vauthors = Ainsworth M |publisher=Johns Hopkins University Press |year=1967 |isbn=978-0-8018-0010-8 |location=Baltimore}}</ref> Anxiety, fear, illness, and fatigue are expected to increase a child's attachment behaviours.{{sfn|Karen|1998|p=97}}

After the second year, Bowlby thought that a child begins to see the caregiver as an independent person. This is Phase Four beginning, and a more complex and goal-corrected partnership develops.{{sfn|Prior|Glaser|2006|pp=19–20}} Children begin to notice others' goals and feelings and plan their actions accordingly.

== Empirical research and theoretical developments ==

=== Attachment behaviours ===
The basic materials for the formation of a baby's hypothetical ''attachment behavioural system'' comprise a limited set of inborn proximity-promoting behaviours which Bowlby called ''attachment behaviours''.<ref>Bowlby (1969) 2nd ed. pp. 244ff.</ref> Influenced by ethology, Bowlby asserted that the attachment behaviours babies emitted in their early months were [[fixed action pattern]]s (FAPs).

[[Fixed action pattern]]s were first identified by [[ethology |ethologists]] in animals like stickleback fish and digger wasps. They were held to be reflexively triggered by a pre-ordained releasing stimulus and not to change in form or direction whatever the circumstances in which the animal found itself. Bowlby translated this as meaning young babies' smiles, cries, looks and sucks were "highly stereotyped" in form and "once initiated, follow their typical course to its completion almost irrespective of what is happening in the environment".<ref>Bowlby (1969) 2nd ed. p.65.</ref>

Observational researchers soon refuted Bowlby's belief that babies' early smiles, looks, reaches, sucks, roots, cries—or later on, their babbling and following—were fixed in form, triggered by only one releasing stimulus, or only had one evolutionary function (that of promoting proximity to mother). On the contrary, all these behaviours have many functions<ref>{{cite journal |last1=Pilkington |first1=Pamela D. |last2=Bishop |first2=Amy |last3=Younan |first3=Rita |title=Adverse childhood experiences and early maladaptive schemas in adulthood: A systematic review and meta-analysis |journal=Clinical Psychology & Psychotherapy |date=May 2021 |volume=28 |issue=3 |pages=569–584 |doi=10.1002/cpp.2533 |pmid=33270299 }}</ref> and vary subtly from occasion to occasion and adapt to the baby's current circumstances.<ref>{{cite book |last1=von Hofsten |first1=C. |last2=Rosander |first2=K. |title=Studying the Perception-Action System as a Model System for Understanding Development |chapter=The Development of Sensorimotor Intelligence in Infants |series=Advances in Child Development and Behavior |date=2018 |volume=55 |pages=73–106 |doi=10.1016/bs.acdb.2018.04.003 |pmid=30031439 |isbn=978-0-12-814763-4 }}</ref>A baby's cries are highly variable in duration, loudness and continuity.<ref name="Pratt 1981">{{cite book |title=Communicating with Normal and Retarded Children |last1=Pratt |first1=Chris |publisher=Wright & Sons |location=London |year=1981 |isbn= 9780723605720 |editor-last1= Fraser |editor-first1=William |editor-last2=Grieve |editor-first2=Robert |pages=3–23 |chapter= Crying in Normal Infants}}</ref> And the smiles of even the youngest infant vary in intensity, direction, eliciting event (sometimes babies smile in their sleep) and duration.<ref>{{cite journal |last1= Messinger |first1= Daniel |last2= Fogel |first2= Alan |title= The Interactive Development of Social Smiling |journal=Advances in Child Behaviour and Development |series= Advances in Child Development and Behavior |date=2007 |volume=35 |pages=327–366 |doi= 10.1016/B978-0-12-009735-7.50014-1 |pmid= 17682330 |isbn= 978-0-12-009735-7 }}</ref> Looking is also a very flexible behaviour and accompanies any intentional action by an infant. Likewise with babbling, which Bowlby listed among attachment behaviours.<ref>{{cite journal |last1= Ollers|first1= Kimbrough |last2= Eilers |first2= Rebecca |title= The Role of Audition in Infant Babbling |journal=Child Development |date=1988 |volume=59 |issue= 2 |pages=441–449 |doi= 10.2307/1130323 |jstor= 1130323 }}</ref>

The fact that the behaviours Bowlby called "attachment behaviours" vary in form and function from birth on means they cannot be [[signal]]s encoded by evolution to promote proximity to a mother-figure, as he claimed.<ref>Bowlby (1969) pp. 314ff.</ref> But they ''can'' function ''as if'' they are signals when they serve to trigger the caregiving behaviour of anyone in their vicinity, that is, what attachment theorists call ''the caregiving behavioural system''.

=== A laboratory procedure ===
True to the principles of ethology, [[John Bowlby]] initially conceptualized infant attachments as observable entities. Not just newborn's ''attachment behaviours'', but the attachment behavioural system which integrated these behaviours, and such behavioural consequences as ''fear of strangers'' and ''separation anxiety'' were all supposed to be directly observable. Upon this basis, [[Mary Ainsworth]] and her colleagues designed a seven-episode laboratory-based  observational procedure for measuring infants' attachments to their mothers called the [[Strange situation |Strange Situation Procedure]] or SSP. They predicted that, once infants have begun to form attachments to their mothers around the end of their first year, they should predictably use her as a secure base from which to explore an unfamiliar room containing attractive toys, and, later, to flee to, when confronted by a "stranger".{{fact|date=November 2025}}

These expectations were not confirmed by their research. Ainsworth's group found that, after a 3-minute period of a mother, her baby and a female stranger sitting together in the laboratory (Episode 3), only one out of ten babies followed their mother to the door—and only one out of five babies cried—when she left her baby alone with the stranger for three minutes (Episode 4). A third of the babies showed no alteration in attachment behaviours between Episodes 3 and 4. Thus, as Ainsworth and her colleagues put it, neither separation anxiety nor stranger fear was "as ubiquitous as anticipated" in the SSP: "separation protest . . . [is] by no means invariably activated by the baby's realization of the mother's departure", and separation from the mother, did not "significantly lower the total number of smiles, nor those directed to the stranger".<ref>{{cite book | vauthors = Ainsworth MD, Blehar M, Waters E, Wall S | date = 2015 | title = Patterns of Attachment: A Psychological Study of the Strange Situation | location = New York | publisher = Psychology Press| pages = 262ff | isbn = 978-1-84872-682-6 }}</ref> So Ainsworth had to conclude ''both'' that attachment behaviours did not constitute an ''attachment behavioural system'' of the kind Bowlby's theory proposed, ''and'' that separation anxiety and fear of strangers could not be used to diagnose whether a baby was attached to his or her caregiver.

In order to avoid jettisoning the theory, these results necessitated a quiet about-face. Rather than attachments being ''directly'' observable, Ainsworth and her colleagues proposed attachments were invisible [[Internal working model of attachment |internal]] structures which existed inside the baby without any easily-predicted or measurable link to his or her observable behaviour.<ref>{{cite book | vauthors = Ainsworth MD, Blehar M, Waters E, Wall S | date = 2015 | title = Patterns of Attachment: A Psychological Study of the Strange Situation | location = New York | publisher = Psychology Press| pages = 295–298 | isbn = 978-1-84872-682-6 }}</ref> This reorientation ushered in a new interpretive approach to attachment, meaning only researchers who have been extensively trained by attachment experts are thought to be able to classify what kind of attachment an infant-adult pair exhibit.

The SSP remains the most widely used means of diagnosing the security or insecurity of infant-adult attachments, and of [[Validity (statistics) |validating]] newer methods such as  the [[Attachment measures | Attachment Q-sort]]. It is a 21-minute procedure. So, over the years, many researchers have queried whether SSP ratings reflect the ''current state'' of infant-adult interaction, something which may vary over days or months. Alternatively, do classifications from the SSP measure a stable ''underlying structure'', namely, the child's attachment to their caregiver, as attachment theory proposes?{{fact|date=November 2025}}

=== Does the Strange Situation Procedure produce reliable results? ===
Psychological tests are [[Reliability (statistics) |reliable]] if they produce similar results under consistent conditions. If the SSP is reliable, it should produce the same attachment classification for an infant-caregiver duo when the test is done twice over a few weeks or months. Studies show the greatest reliability of attachment ratings from the SSP when the social background of the infant's family remains stable between the two assessments: socio-economically; maritally; in terms of social support; housing; and childcare provision. And vice versa: when a baby's social background changes between two SSP ratings, the ratings are likely to change.
SSP classifications are especially volatile when researchers make the effort to recruit to their studies infants who do not come from intact middle-class families and whose parents have not volunteered to participate.<ref name="Lamb">{{cite journal |last1=Lamb |first1=Michael E. |last2=Thompson |first2=Ross A. |last3=Gardner |first3=William P. |last4=Charnov |first4=Eric L. |last5=Estes |first5=David |title=Security of infantile attachment as assessed in the 'strange situation': Its study and biological interpretation |journal=Behavioral and Brain Sciences |date=March 1984 |volume=7 |issue=1 |pages=127–147 |doi=10.1017/S0140525X00026522 }}</ref><ref name="Lamb 1985">{{cite book |editor-first1=Michael E. |editor-first2=Ross A. |editor-first3=William |editor-first4=Eric L. |editor-last1=Lamb |editor-last2=Thompson |editor-last3=Gardner |editor-last4=Charnov |title=Infant-Mother Attachment |date=2013 |doi=10.4324/9780203781791 |isbn=978-1-134-92918-4 }}{{pn|date=November 2025}}</ref><ref name="Booth LaForce 2021">{{cite book |title=Attachment: The Fundamental Questions |last1=Booth LaForce |first1=Cathryn |last2=Roisman |first2=Glenn |publisher=Guildford |location=New York |year=2021 |isbn= 978-1-4625-4602-2 |editor-last1= Thompson |editor-first1=Ross |editor-last2=Simpson |editor-first2=Jeffrey |editor-last3=Berlin |editor-first3=Lisa |pages=154–160 |chapter=Stability and Change in Attachment Security}}</ref><ref>{{cite journal |last1=De Wolff |first1=Marianne |last2=Van IJzendoorn |first2=Marinus |title= Sensitivity and Attachment: A Meta-Analysis on Parental Antecedents of Infant Attachment |journal=Child Development |date=1997 |volume=68 |issue=4 |pages=571–591 |doi=10.1111/j.1467-8624.1997.tb04218.x |pmid=9306636 }}</ref> 

An important corollary of this finding is that attachment studies which ''do not'' [[Scientific control |control]] for a family's social background, may produce results which, for example, seem to show levels of security in attachment classification have a strong positive [[Correlation does not imply causation |correlation]] with a factor like maternal sensitivity, when, in fact, levels of security and sensitivity are both caused by other unstudied factors from their social background. This means that the results of correlational studies which seem to prove the long-term effects of an infant's attachment classification cannot be taken at face-value if those studies were [[Scientific control |uncontrolled]]: the strength of correlations is likely to have been inflated by one or more of the unstudied background variables. One of the background variables most often missing from attachment studies using the SSP is social support. Even when studies do assess some types of environmental risk, they often miss out social support. Yet social support has powerful effects on improving caregiving behaviour, both in low and high-risk families.<ref>{{cite journal |last1=Howes |first1=Carollee |last2=Guerra |first2=Alison |title= Networks of Attachment Relationships in Low-Income Children of Mexican Heritage: Infancy through Preschool |journal=Social Development |date=2009 |volume=18 |issue=4 |pages=896–914 |doi=10.1111/j.1467-9507.2008.00524.x}}</ref><ref>{{cite journal |last1=Raikes |first1=Abigail |last2=Thompson |first2=Ross |title= Links between Risk and Attachment Security: Models of Influence |journal= Applied Developmental Psychology |date=2005 |volume=26 |issue=4 |pages=440–455 |doi=10.1016/j.appdev.2005.04.003}}</ref> 

Though most attachment studies are correlational, some studies do try to prove ''direct'' causal effects of maternal behaviour on infants' attachment security by interventions aimed to improve maternal care. Yet the results of these studies cannot be taken as proven when the studies producing them have not controlled for [[Placebo |placebo effects]].<ref>{{cite journal |last1= Bakermans-Kranenberg |first1=Marian |last2=Van IJzendoorn |first2= Marinus |last3=Juffer |first3=Femmie |title=Less is More: Meta-Analyses of Sensitivity and Attachment Interventions in Early Childhood |journal= Psychological Bulletin |date=2003 |volume=129 |issue=2 |pages=195–215 |doi=10.1037/0033-2909.129.2.195 |pmid=12696839 }}</ref><ref>{{cite journal |last1=Boldt |first1=Lea |last2=Goffin |first2=Kathryn|last3=Kochanska |first3=Grazyna |title=The Significance of Early Parent-Child Attachment for Emerging Regulation: A Longitudinal Investigation of Processes and Mechanisms from Toddler Age to Preadolescence |journal=Developmental Psychology |date=2020 |volume=56 |issue=3 |pages=431–443 |doi=10.1037/dev0000862 |pmid=32077715 |pmc=7041853 }}</ref>

In sum, as [[Michael Lamb (psychologist)|Michael Lamb]] and his coworkers concluded in the 1980s, classifications of attachment in/security derived from the SSP cannot be taken as primarily reflecting the existence of an ''internal'' system or working model in the young child. They are far more likely to be reflecting what has recently been happening in the social world ''external'' to the infant and her or his mother-figure(s) at the times of their assessment.

=== Do infant attachments predict adult behaviour? ===
As might be expected from research which shows that the short-term reliability of the SSP depends largely on the continuing stability of social background variables, the best-known [[longitudinal study |studies]] to have researched the long-term effects/correlates of infant-caregiver bonds on grown-up functions have all failed to produce the kinds of result attachment theory predicts. This is especially true in studies which have controlled for the continuity and discontinuity of background variables experienced by the child while she or he was developing.<ref>{{cite book |title=Attachment from Infancy to Adulthood: The Major Longitudinal Studies |publisher=Guildford |location=New York |year=2006 |isbn= 978-1-4625-4602-2 |editor-last1=Grossman |editor-first1=Klaus |editor-last2=Grossman |editor-first2=Karin |editor-last3=Waters |editor-first3=Everett }}</ref> One longitudinal study in Minnesota showed that, if background variables were properly taken into account, attachment security in infancy only accounted for 5% of the [[variance |variability]] in social competence when the study-children had reached the age of nineteen. Two well-known German studies also failed to find any significant correlation between security of attachment (as measure in the SSP) in toddlers and a variety of measures of social relating after age ten. Long-term Israeli research also found that continuity in attachment representation correlated strongly with the stability of the caregiver's environment, and discontinuity with instability. 

Taken altogether, such findings demonstrate that, when studies using SSP measures include measures of an infant's social circumstances, there can be a strong link to grown-up outcomes—accounting for ''half'' the [[variance]] in the 'Minnesota' longitudinal study when, by themselves, attachment measures account for as little as ''one twentieth'' of the variance.<ref>{{cite journal |last1=Rutter |first1=Michael |title=Critical Notice |journal=Journal of Child Psychology and Psychiatry |date=2006 |volume=47 |pages=974–977 |doi=10.1111/j.1469-7610.2006.01644.x }}</ref>

=== From a theory of infancy to a theory of caregiving ===
Over decades the weakness of the empirical data supporting Bowlby's original observational claims about infants has necessitated a greater emphasis in attachment theory on caregiving. According to his first formulation, Bowlby had argued that the attachment behavioural system (ABS) of modern infants evolved to protect infants against danger: when a Stone Age baby was in peril, it would maximise its chances of surviving by seeking proximity to its mother, and, as a result so-called attachment behaviours would have evolved, the better to maintain a baby's closeness to their mother in times of illness, danger, or stress. However, the ABS cannot have been what helped to guarantee a baby's survival, given that, according to Bowlby, the ABS is not fully functional until after a child turns three: it is around 30 months of age that a "mutual" goal-corrected partnership between child and caregiver becomes stabilised. Furthermore, in Bowlby's theory, the attachment behaviours stereotypically 'emitted' during early infancy cannot be adjusted to circumstances. Hence, even by Bowlby's own lights, the ABS cannot have ensured infants' survival during the pre-human era, nor in ours. Rather, infant security must have depended on the vigilance, responsiveness and intelligence of caregivers, or what attachment theorists now call the caregiving behavioural system. Which renders superfluous Bowlby's evolutionary rationale for the presence of a specially-evolved ABS in infants.{{fact|date=November 2025}}

Attachment theory's attractiveness initially derived from the scientific credentials it gave to post-World War Two child-centeredness. And, in that vein, its message was principally aimed at caregivers and policy-makers. Even the SSP, while supposedly focused on infant behaviour, is, as Marga Vicedo observes, primarily used as a way of identifying better and worse kinds of caregiving.<ref>{{cite journal |last1= Vicedo|first1= Marga |title=Putting Attachment in its Place: Disciplinary and Cultural Contexts' |journal=European Journal of Developmental Psychology |date=2017 |volume=14 |issue= 6 |pages=684–699 |doi= 10.1080/17405629.2017.1289838 }}</ref><ref name="Vicedo 2017">{{cite book |title= The Cultural Nature of Attachment: Contextualizing Relationships and Development |last1=Vicedo |first1=Marga |publisher=MIT Press |location=Cambridge |year=2017 |isbn= 978-0-262-03690-0 |editor-last1=Keller|editor-first1=Heidi |editor-last2=Bard |editor-first2=Kim | pages=13–51 |chapter=The Strange Situation of the Ethological Theory of Attachment: A Historical Perspective}}</ref> In this light, and the light of careful empirical research, the status of attachment classifications is now probably best seen as valuably ''descriptive'' of a range of different kinds of infant-caregiver bond in certain cultures, not as independently predictive nor as universally explanatory.

==Attachment patterns==
{{Main|Strange situation |Attachment in children}}
[[File:Adult attachment patterns.svg|thumb|Attachment theory styles]]
{{blockquote|The strength of a child's attachment behaviour in a given circumstance does not indicate the "strength" of the attachment bond. Some insecure children will routinely display very pronounced attachment behaviours, while many secure children find that there is no great need to engage in either intense or frequent shows of attachment behaviour.<ref>Howe, D. (2011) Attachment across the lifecourse, London: Palgrave, p.13</ref>}} 
{{blockquote|Individuals with different attachment styles have different beliefs about romantic love period, availability, trust capability of love partners and love readiness.<ref>{{cite journal | vauthors = Honari B, Saremi AA | year = 2015 | title = The Study of Relationship between Attachment Styles and Obsessive Love Style | journal = Procedia - Social and Behavioral Sciences | volume = 165 | pages = 152–159 | doi = 10.1016/j.sbspro.2014.12.617 | doi-access = free }}</ref>}}

=== Secure attachment ===
{{See also|Secure attachment}}

A child who is securely attached to its parent will explore and play freely while the caregiver is present, using them as a "secure base" from which to explore. The child will engage with the stranger when the caregiver is present, and may be visibly upset when the caregiver departs but happy to see the caregiver on their return. The child feels confident that the caregiver is available, and will be responsive to their attachment needs and communications.<ref name="Ainsworth, M.D.S, Blehar, M. C., Waters, E., & Wall, S.">{{cite book | vauthors = Ainsworth MD, Blehar MC, Waters E, Wall S | date = 1978 | title =  Patterns of attachment: A psychological study of the strange situation. | location = Hillsdale, NJ | publisher = Earlbaum }}</ref><ref>[[Daniel Schacter|Schacter, D.L.]] et al. (2009). Psychology, Second Edition. New York: Worth Publishers. pp.441</ref>

=== Anxious-ambivalent attachment ===
Children classified as Anxious-ambivalent attachment show a form of insecure attachment which is also sometimes called "resistant attachment".<ref name="Ainsworth,1978a">{{cite book |title=Patterns of Attachment: A Psychological Study of the Strange Situation |vauthors=Ainsworth MD, Blehar M, Waters E, Wall S |publisher=Lawrence Erlbaum Associates |year=1978 |isbn=978-0-89859-461-4 |location=Hillsdale NJ}}</ref><ref name="Plotka 2011 pp. 81–83">{{cite book | last=Plotka | first=Raquel | title=Encyclopedia of Child Behavior and Development | chapter=Ambivalent Attachment | publisher=Springer US | publication-place=Boston, MA | year=2011 | doi=10.1007/978-0-387-79061-9_104 | pages=81–83| isbn=978-0-387-77579-1 |quote=Ambivalent attachment is a form of insecure attachment characterized by inconsistent responses of the caregivers and by the child's feelings of anxiety and preoccupation about the caregiver's availability.}}</ref>Ambivalent/Resistant (C) showed distress even before separation, and were clingy and difficult to comfort on the caregiver's return.<ref>{{cite journal |last1=Cassidy |first1=Jude |last2=Berlin |first2=Lisa J. |title=The Insecure/Ambivalent Pattern of Attachment: Theory and Research |journal=Child Development |date=1994 |volume=65 |issue=4 |pages=971–991 |doi=10.1111/j.1467-8624.1994.tb00796.x |jstor=1131298 }}</ref> They showed either signs of resentment in response to the absence (C1 subtype), or signs of helpless passivity (C2 subtype). Hans et al. have expressed concern that "ambivalent attachment remains the most poorly understood of Ainsworth's attachment types".<ref>{{cite book |last1=Hans |first1=Sydney L |last2=Bernstein |first2=Victor J |last3=Sims |first3=Belinda E |chapter=Change and Continuity in Ambivalent Attachment Relationships from Infancy through Adolescence |page=279 |chapter-url={{GBurl|pAWQU0WFWwMC|p=279}} |editor1-last=Crittenden |editor1-first=Patricia McKinsey |editor2-last=Claussen |editor2-first=Angelika Hartl |title=The Organization of Attachment Relationships: Maturation, Culture, and Context |date=2003 |publisher=Cambridge University Press |isbn=978-0-521-53346-1 }}</ref> In particular, the relationship between ambivalent/resistant (C) and disorganisation (D) is still to be clarified.<ref>{{cite journal |last1=Mayseless |first1=Ofra |title=Maternal caregiving strategy—a distinction between the ambivalent and the disorganized profile |journal=Infant Mental Health Journal |date=1998 |volume=19 |issue=1 |pages=20–33 |doi=10.1002/(SICI)1097-0355(199821)19:1<20::AID-IMHJ2>3.0.CO;2-3 }}</ref> However, researchers agree that the Anxious-Ambivalent/Resistant strategy is a response to unpredictably responsive caregiving, and that the displays of anger or helplessness towards the caregiver on reunion can be regarded as a conditional strategy for maintaining the availability of the caregiver by preemptively taking control of the interaction.<ref>{{cite journal |last1=Solomon |first1=Judith |last2=George |first2=Carol |last3=De Jong |first3=Annemieke |title=Children classified as controlling at age six: Evidence of disorganized representational strategies and aggression at home and at school |journal=Development and Psychopathology |date=1995 |volume=7 |issue=3 |pages=447–463 |doi=10.1017/S0954579400006623 }}</ref><ref>{{cite journal |last1=Crittenden |first1=Patricia McKinsey |authorlink1=Patricia McKinsey Crittenden |title=Danger and Development: The Organization of Self-Protective Strategies |journal=Monographs of the Society for Research in Child Development |date=1999 |volume=64 |issue=3 |pages=145–171 |doi=10.1111/1540-5834.00037 |jstor=3181562 }}</ref>

=== Anxious-avoidant attachment ===
A child with the anxious-avoidant insecure attachment pattern will avoid or ignore the caregiver, showing little emotion when the caregiver departs or returns. The child will not explore very much regardless of who is there. Infants classified as anxious-avoidant (A) represented a puzzle in the early 1980s. They did not exhibit distress on separation, and either ignored the caregiver on their return (A1 subtype) or showed some tendency to approach together with some tendency to ignore or turn away from the caregiver (A2 subtype). Ainsworth and Bell theorised that the apparently unruffled behaviour of the avoidant infants is in fact a mask for distress, a hypothesis later evidenced through studies of the heart rate of avoidant infants.<ref>{{cite journal |last1=Ainsworth |first1=Mary D. Salter |last2=Bell |first2=Silvia M. |title=Attachment, Exploration, and Separation: Illustrated by the Behavior of One-Year-Olds in a Strange Situation |journal=Child Development |date=1970 |volume=41 |issue=1 |pages=49–67 |doi=10.2307/1127388 |jstor=1127388 |pmid=5490680 }}</ref><ref>{{cite journal |last1=Sroufe |first1=L. Alan |last2=Waters |first2=Everett |title=Attachment as an Organizational Construct |journal=Child Development |date=1977 |volume=48 |issue=4 |pages=1184–1199 |doi=10.2307/1128475 |jstor=1128475 }}</ref>

=== {{Anchor|disorganized attachment}}Disorganized-disoriented attachment ===
Beginning in 1983, Crittenden offered A/C and other new organized classifications (see below). Drawing on records of behaviours discrepant with the A, B and C classifications, a fourth classification was added by Ainsworth's colleague Mary Main.<ref name=":0">{{cite book |title=Attachment in the Preschool Years: Theory, Research, and Intervention |last1=Main |first1=Mary |last2=Solomon |first2=Judith |publisher=University of Chicago Press |year=1990 |isbn=978-0-226-30630-8 |editor-last=Greenberg |editor-first=Mark T. |location=Chicago |pages=121–60 |chapter=Procedures for Identifying Infants as Disorganized/Disoriented during the Ainsworth Strange Situation |editor2-last=Cicchetti |editor2-first=Dante |editor3-last=Cummings |editor3-first=E. Mark |chapter-url=https://books.google.com/books?id=WzHIfiCXE8EC&pg=PA121}}</ref> In the Strange Situation, the attachment system is expected to be activated by the departure and return of the caregiver. If the behaviour of the infant does not appear to the observer to be coordinated in a smooth way across episodes to achieve either proximity or some relative proximity with the caregiver, then it is considered 'disorganized' as it indicates a disruption or flooding of the attachment system (e.g. by fear). Infant behaviours in the Strange Situation Protocol coded as disorganized/disoriented include overt displays of fear; contradictory behaviours or affects occurring simultaneously or sequentially; stereotypic, asymmetric, misdirected or jerky movements; or freezing and apparent dissociation. Lyons-Ruth has urged, however, that it should be more widely "recognized that 52% of disorganized infants continue to approach the caregiver, seek comfort, and cease their distress without clear ambivalent or avoidant behavior"<!-- Presuming spelling from the original -->.<ref name="Lyons-Ruth Bureau Easterbrooks 2013">{{cite journal |last1=Lyons-Ruth |first1=Karlen |last2=Bureau |first2=Jean-Francois |last3=Easterbrooks |first3=M. Ann |last4=Obsuth |first4=Ingrid |last5=Hennighausen |first5=Kate |last6=Vulliez-Coady |first6=Lauriane |title=Parsing the construct of maternal insensitivity: distinct longitudinal pathways associated with early maternal withdrawal |journal=Attachment & Human Development |date=November 2013 |volume=15 |issue=5–6 |pages=562–582 |doi=10.1080/14616734.2013.841051 |pmid=24299135 |pmc=3861901 }}</ref>

=== Reactive attachment disorder and attachment disorder ===
{{Main|Reactive attachment disorder|Attachment disorder}}
One atypical attachment pattern is considered to be an actual disorder, known as ''reactive attachment disorder'' or RAD, which is a recognized psychiatric diagnosis ([[ICD-10]] F94.1/2 and [[DSM-IV-TR]] 313.89). Against common misconception, this is not the same as 'disorganized attachment'. The essential feature of reactive attachment disorder is markedly disturbed and developmentally inappropriate social relatedness in most contexts that begins before age five years, associated with gross pathological care. <ref name="schecter">{{cite journal | vauthors = Schechter DS, Willheim E | title = Disturbances of attachment and parental psychopathology in early childhood | journal = Child and Adolescent Psychiatric Clinics of North America | volume = 18 | issue = 3 | pages = 665–86 | date = July 2009 | pmid = 19486844 | pmc = 2690512 | doi = 10.1016/j.chc.2009.03.001 }}</ref>

=== The dynamic-maturational model ===
{{Main|Dynamic-maturational model of attachment and adaptation}}
The dynamic-maturational model of attachment and adaptation is a [[biopsychosocial model]] describing the effect attachment relationships can have on human development and functioning. It is especially focused on the effects of relationships between children and parents and between reproductive couples. The DMM was initially created by developmental psychologist [[Patricia McKinsey Crittenden]] and her colleagues including David DiLalla, Angelika Claussen, Andrea Landini, Steve Farnfield, and Susan Spieker.

=== Significance of patterns ===
Research based on data from longitudinal studies, such as the [[National Institute of Child Health and Human Development|National Institute of Child Health and Human Development Study of Early Child Care]] and the Minnesota Study of Risk and Adaption from Birth to Adulthood, and from cross-sectional studies, seeking to show associations between early attachment classifications and peer relationships typically fails to control for social background variables when seeking correlations between attachment classifications and other child behaviours, such as competence with peers. This is a general problem. Lyons-Ruth, for example, found that 'for each additional withdrawing behavior displayed by mothers in relation to their infant's attachment cues in the Strange Situation Procedure, the likelihood of clinical referral by service providers was increased by 50%.'<ref name="Lyons-Ruth Bureau Easterbrooks 2013"/> But no attempt was made to assess the social background of the children who had better or worse outcomes. Similar problems infect most longitudinal claims about secure children, for example, that they have more positive and fewer negative peer reactions and establish more and better friendships. 

The possibility that infants are competent in peer-groups ''before'' nine months of age (before caregiver-focused attachments have formed) has never been investigated in attachment research. Such group-interactional competence is now proven in babies as young as six months old.<ref>{{cite journal |last1=Chamberlain |first1=Michaela |title=Babies in Groups: A Review |journal=British Journal of Psychotherapy |date=2025 |volume=41 |pages=589–593 |doi=10.1111/bjp.12959 }}</ref> As a result, we may now ask whether attachment-formation is itself a consequence of how much experience pre-attachment babies have of interacting in groups, in [[extended family |extended families]] versus [[nuclear families]] for example.

Few if any rigorous studies which control for social background variables of the children they compare show even a weak association between early experience and any comprehensive measure of social functioning in early adulthood.<ref>{{cite book |title=Attachment from Infancy to Adulthood: The Major Longitudinal Studies |publisher=Guildford |location=New York |year=2006 |isbn= 978-1-4625-4602-2 |editor-last1=Grossman |editor-first1=Klaus |editor-last2=Grossman |editor-first2=Karin |editor-last3=Waters |editor-first3=Everett }}</ref><ref>{{cite journal |last1=Rutter |first1=Michael |title=Critical Notice |journal=Journal of Child Psychology and Psychiatry |date=2006 |volume=47 |pages=974–977 |doi=10.1111/j.1469-7610.2006.01644.x }}</ref> However, in studies which ignore social background, early experience may seem to predict early childhood representations of relationships, which in turn may be held to correlate with later self and relationship representations and social behaviour.

==Changes in attachment during childhood and adolescence==
{{Main |Attachment in children}}
Attachment theory holds that childhood and adolescence allows the development of an internal working model useful for forming attachments. This internal working model is hypothesized to relate to the individual's state of mind which develops with respect to attachment generally and explores how attachment functions in relationship dynamics based on childhood and adolescent experience. The organization of an internal working model is generally seen as leading to more stable attachments in those who develop such a model, rather than those who rely more on the individual's state of mind alone in forming new attachments.<ref>{{cite journal |last1=Main |first1=Mary |last2=Kaplan |first2=Nancy |last3=Cassidy |first3=Jude |title=Security in Infancy, Childhood, and Adulthood: A Move to the Level of Representation |journal=Monographs of the Society for Research in Child Development |date=1985 |volume=50 |issue=1/2 |pages=66–104 |doi=10.2307/3333827 |jstor=3333827 }}</ref> Age, cognitive growth, and continued social experience advance the development and complexity of the internal working model.

== Cultural differences ==
In Western cultures of child-rearing, there is a focus on single attachment to primarily the mother. This dyadic model is not the only strategy of attachment producing a secure and emotionally adept child. Having a single, dependably responsive and sensitive caregiver (namely the mother) does not guarantee the ultimate success of the child. Results from Israeli, Dutch and east African studies show children with multiple caregivers grow up not only feeling secure, but developed "more enhanced capacities to view the world from multiple perspectives."<ref name=":12">{{cite book |title=Mothers and Others-The Evolutionary Origins of Mutual Understanding |url=https://archive.org/details/mothersothersevo0000hrdy |last=Hrdy |first=Sarah Blaffer |publisher=The Belknap Press of Harvard University Press |year=2009 |isbn=978-0-674-03299-6 |location=United States of America |pages=[https://archive.org/details/mothersothersevo0000hrdy/page/130 130], 131, 132}}</ref> This evidence can be more readily found in hunter-gatherer communities, like those that exist in rural Tanzania.<ref>{{Citation|last1=Crittenden|first1=Alyssa N.|title=Cooperative Child Care among the Hadza: Situating Multiple Attachment in Evolutionary Context|date=2013|work=Attachment Reconsidered|pages=67–83|publisher=Palgrave Macmillan US|isbn=978-1-137-38674-8|last2=Marlowe|first2=Frank W.|doi=10.1057/9781137386724_3}}</ref>

In hunter-gatherer communities of the past and present, mothers may be the primary caregivers, but not in the same way as a stay-at-home mother in Western cultures. Some Australian Aboriginal languages do not distinguish mothers, calling them 'aunt.' This reflects the fact that a baby's adult kin share parental responsibilities for ensuring a child's survival with a variety of different [[Allomothering|allomothers]]. So while a mother is important, she does not offer the only opportunity for care and security. Several group members (with or without blood relation) contribute to the task of bringing up a child, sharing the parenting role and therefore can be sources of multiple relationships and attachments. There is evidence of this communal parenting throughout history that "would have significant implications for the evolution of multiple attachment."<ref>{{cite book |title=Attachment Reconsidered: Cultural Perspectives on a Western Theory |last1=Quinn |first1=Naomi |last2=Mageo |first2=Jeannette Marie |publisher=Palgrave Macmillan |year=2013 |isbn=978-1-137-38672-4 |location=United States of America |pages=73, 74}}</ref>

In rural India where a family typically consists of 3 generations (and sometimes 4: great-grandparents, grandparents, parents, and child or children), the child or children would have four to six caregivers from whom to select their favourite "attachment figure". A child's "uncles and aunts" (parents' siblings and their spouses) contribute significantly to the child's and the mother's psycho-social enrichment.<ref>{{cite book |last1=Parens |first1=Henri |title=Parenting for Emotional Growth |date=1995 |url=https://jdc.jefferson.edu/parentingemotionalgrowth/1/ }}{{pn|date=November 2025}}</ref>

Even in Western and Westernised cultures, deviations from the behaviour of American mothers and babies in the Strange Situation Protocol have been observed. A study of 60 Japanese mother-infant pairs compared them with Ainsworth's distributional pattern. Although the ranges for securely attached and insecurely attached had no significant differences in proportions, the Japanese insecure group consisted of only resistant children, with no children categorized as avoidant.<ref >{{cite journal | vauthors = Takahashi K |year=1986 |title=Examining the strange-situation procedure with Japanese mothers and 12-month-old infants| journal=Developmental Psychology |volume=22 |issue=2 |pages=265–270 |doi=10.1037/0012-1649.22.2.265 }}</ref>  This may be because the Japanese child rearing philosophy stressed close mother infant bonds more so than in Western cultures.  A Northern German study replicated the Ainsworth Strange Situation with 46 mother-infant pairs and found a distribution of attachment classifications different from North America, with a high number of avoidant infants: 52% avoidant, 34% secure, and 13% resistant.<ref>{{cite journal |last1=Grossman |first1=Karin |last2=Grossman |first2=Klaus|last3= Spangler |first3=Gottfried | last4=Suess  |first4=Gerhard  |last5=Unzner  |first5=Lothar|title= Maternal Sensitivity and Newborns' Orientation Responses as Related to Quality of Attachment in Northern Germany |journal= Monographs of the Society for Research in Child Development |date=1985 |volume=50 |issue=1–2 |pages=233–256 |doi=10.2307/3333836 |jstor=3333836 |pmid=4069129 }}</ref>

While all children require a secure social environment and strong relationships for healthy development, the kinds of social milieux and close relationships available vary widely around the world. They may sometimes involve just one parent but will far more often involve aunts and uncles, grandparents, cousins, siblings and peer groups. Viewed through the lens of attachment theory, children born into Western societies may seem to require only one kind of relationship for healthy development. But cross-cultural research suggests that multiple lenses are needed to appreciate the varied routes to a flourishing adulthood available around the world.<ref >{{cite book |title= The Cultural Nature of Attachment: Contextualizing Relationships and Development |publisher=MIT Press |location=Cambridge |year=2017 |isbn= 978-0-262-03690-0 |editor-last1=Keller|editor-first1=Heidi |editor-last2=Bard |editor-first2=Kim }}{{pn|date=November 2025}}</ref><ref>{{cite book |title=The Myth of Attachment Theory: A Critical Understanding for Multicultural Societies |publisher=Routledge |location=London |year=2021 |isbn= 978-1-00-316709-9 |author-last1=Keller |author-first1=Heidi  }}{{pn|date=November 2025}}</ref>

==Attachment styles in adults==
{{Main|Attachment in adults}}{{See also|Attachment measures}}
Attachment theory was extended to adult [[romantic relationship]]s in the late 1980s by Cindy Hazan and [[Phillip Shaver]].<ref>{{cite journal |last1=Hazan |first1=Cindy |last2=Shaver |first2=Phillip |title=Romantic love conceptualized as an attachment process. |journal=Journal of Personality and Social Psychology |date=1987 |volume=52 |issue=3 |pages=511–524 |doi=10.1037/0022-3514.52.3.511 |pmid=3572722 }}</ref> Four styles of attachment have been identified in adults: secure, anxious-preoccupied, dismissive-avoidant and fearful-avoidant. These roughly correspond to infant classifications: secure, insecure-ambivalent, insecure-avoidant and disorganized/disoriented.<ref>{{cite journal |last1=Hazan |first1=Cindy |last2=Shaver |first2=Phillip R. |title=Love and work: An attachment-theoretical perspective. |journal=Journal of Personality and Social Psychology |date=August 1990 |volume=59 |issue=2 |pages=270–280 |doi=10.1037/0022-3514.59.2.270 }}</ref> Adult attachment styles are related to individual differences in the ways in which adults experience and manage their emotions. Recent meta-analyses link insecure attachment styles to lower [[emotional intelligence]]<ref>{{cite journal |last1=Walker |first1=Sarah A. |last2=Double |first2=Kit S. |last3=Kunst |first3=Hannah |last4=Zhang |first4=Michael |last5=MacCann |first5=Carolyn |title=Emotional intelligence and attachment in adulthood: A meta-analysis |journal=Personality and Individual Differences |date=January 2022 |volume=184 |article-number=111174 |doi=10.1016/j.paid.2021.111174 |url=https://durham-repository.worktribe.com/output/2229925 }}</ref> and lower trait mindfulness.<ref>{{cite journal |last1=Stevenson |first1=Jodie C. |last2=Emerson |first2=Lisa-Marie |last3=Millings |first3=Abigail |title=The Relationship Between Adult Attachment Orientation and Mindfulness: a Systematic Review and Meta-analysis |journal=Mindfulness |date=December 2017 |volume=8 |issue=6 |pages=1438–1455 |doi=10.1007/s12671-017-0733-y |pmc=5693974 |pmid=29201245 }}</ref>

==History==
{{Main|History of attachment theory}}

Attachment theory rode a post-World War 2 wave in Westernized countries toward child-centred parenting. The child-centred message of [[Benjamin Spock]]'s post-war manual [[The Common Sense Book of Baby and Child Care]], first published in 1946, put it among the best-selling books of the twentieth century. Previous experts had warned parents not to spoil babies through [[behaviourism |rewarding]] them for crying by picking them up and comforting them, or by feeding them on demand. Babies should be fed once every four hours and otherwise left to cry it out. Spock saw such parenting as cruel. His manual promoted flexibility in child-rearing, advising parents to treat each child as an individual and emphasizing that, ultimately, the parents' common sense and their "natural loving care" were the keys to successful parenting.<ref>{{cite book |title= The Common Sense Book of Baby and Child Care  |publisher= Duell, Sloan, and Pearce |location=New York |year=1946 |isbn= 067102194X |author-last1=Spock |author-first1=Benjamin  }}</ref>
A similar [[structure of feeling]] emerged in post-war Britain.

=== Formulation of the theory ===
Following the publication of ''Maternal Care and Mental Health'',<ref name="Bowlby 86">{{cite web |url=http://www.garfield.library.upenn.edu/classics1986/A1986F063100001.pdf |title=Citation Classic, ''Maternal Care and Mental Health'' | vauthors = Bowlby J |date=December 1986 |publisher=Current Contents |access-date=July 13, 2008 |volume=50 |issue=18}}</ref> Bowlby sought new understanding from the fields of evolutionary biology, ethology, [[developmental psychology]], [[cognitive science]] and the theory of control systems. He formulated the innovative proposition that mechanisms underlying an infant's emotional tie to the caregiver(s) were not learnt, but emerged as a result of [[evolutionary pressure]]. He set out to develop a theory of motivation and behaviour-control built on observational science rather than Freudian interpretation. Bowlby argued that with attachment theory he had made good the "deficiencies of the data and the lack of theory to link alleged cause and effect" of ''Maternal Care and Mental Health''.

=== Psychoanalysis ===
Bowlby was trained as a [[psychoanalysis |psychoanalyst]] under the supervision of [[Melanie Klein]] in the school of [[object relations theory]]. Unlike Freudian theory, which holds that infants are born into a state of ''primary narcissism'' that makes social relations with other people impossible, object relations theory proposes that babies have emotional relations with their mother from the start of life, albeit dominated by phantasy. Thus Bowlby was educated to believe that the infant-mother relationship is of supreme importance to human  beings from the dawn of life, a belief that attachment theory celebrates.

=== Ethology ===
One of the main lessons Bowlby drew from [[ethology]] was the importance of the direct observation of animals in their 'home' environments to scientific theory-building. Thus he constantly stressed the advantages of basing his theory of infancy on verifiable observations of babies' action patterns, rather than psychoanalytic reconstruction of their fantasy lives. After Bowlby's attention was drawn to ethology in the early 1950s by reading [[Konrad Lorenz]]'s work,<ref>{{cite journal |last=Bretherton |first=Inge |year=1992 |title=The origins of attachment theory: John Bowlby and Mary Ainsworth |url=http://www.psychology.sunysb.edu/attachment/online/inge_origins.pdf |journal=Developmental Psychology |volume=28 |issue=5 |pages=759–775 |doi=10.1037/0012-1649.28.5.759}}</ref> he imported several ethological concepts into attachment theory including [[fixed action pattern |fixed action patterns]], instincts and later, behavioural systems. He also took from ethology the importance of recognizing the evolutionary origins of human social behaviour, particularly in infants.

Initially Bowlby imported the ethological concepts of [[Imprinting (psychology)|imprinting]] and [[critical period |critical periods]] into his theory. He was particularly impressed by [[Konrad Lorenz|Konrad Lorenz's]] findings about [[Imprinting (psychology)|imprinting]] in ducklings and goslings. So he hypothesised that there was a [[Critical period|sensitivity period]] during which this attachment system best operated, lasting from six weeks to twelve months of age. However, over time, research proved there were more differences than similarities between attachment behaviours in human babies and imprinting in waterbirds, so the analogy was dropped.<ref name="Rutter 95" /><ref>{{Cite journal|last=McLeod|first=Saul|date=5 February 2017|title=Bowlby's Attachment Theory|url=https://www.simplypsychology.org/bowlby.html|website=Simply Psychology}}</ref>

=== Cybernetics ===
The theory of control systems ([[cybernetics]]), developing during the 1930s and 1940s, influenced Bowlby's thinking.<ref name="Robbins">{{cite journal | vauthors = Robbins P, Zacks JM | title = Attachment theory and cognitive science: commentary on Fonagy and Target | journal = Journal of the American Psychoanalytic Association | volume = 55 | issue = 2 | pages = 457–67; discussion 493–501 | year = 2007 | pmid = 17601100 | doi = 10.1177/00030651070550021401 }}</ref> The young child's need for proximity to the attachment figure was seen as balancing [[Homeostasis|homeostatically]] with the need for exploration. (Bowlby compared this process to physiological homeostasis whereby, for example, blood pressure is kept within limits). The actual distance maintained by the child would vary as the balance of needs changed. For example, the approach of a stranger, or an injury, would cause the child exploring at a distance to seek proximity. The child's goal is not an object (the caregiver) but a state; maintenance of the desired distance from the caregiver depending on circumstances.<ref name="Cassidy"/>

=== Cognitive development ===
Bowlby's reliance on [[Jean Piaget|Piaget]]'s theory of cognitive development gave rise to questions about object permanence (the ability to remember an object that is temporarily absent) in early attachment behaviours. An infant's ability to discriminate strangers and react to the mother's absence seemed to occur months earlier than Piaget suggested would be cognitively possible.<ref name="fraiberg">{{cite journal | vauthors = Fraiberg S | title = Libidinal object constancy and mental representation | journal = The Psychoanalytic Study of the Child | volume = 24 | pages = 9–47 | year = 1969 | pmid = 5353377 | doi = 10.1080/00797308.1969.11822685 }}</ref> More recently, it has been noted that the understanding of mental representation has advanced so much since Bowlby's day that present views can be more specific than those of Bowlby's time.<ref name="waters2">{{cite journal | vauthors = Waters HS, Waters E | title = The attachment working models concept: among other things, we build script-like representations of secure base experiences | journal = Attachment & Human Development | volume = 8 | issue = 3 | pages = 185–97 | date = September 2006 | pmid = 16938702 | doi = 10.1080/14616730600856016 }}</ref>

=== Internal working model ===
{{Main |Internal working model of attachment}}
Bowlby discovered the ''internal working model'' construct in the writings of an eminent scientist interested in the neural basis of animal memory, [[John Zachary Young]], while rethinking what he considered to be scientifically outdated explanations of the psychoanalytic "internal world."<ref>{{cite book | vauthors = Cassidy J | chapter = The Nature of a Child's Ties. | veditors = Cassidy J, Shaver PR | title = Handbook of attachment: Theory, research, and clinical applications. | url = https://archive.org/details/handbookofattach0000unse_n9k8 | edition = 2nd | location = New York, NY | publisher = Guilford Press | date = 2008 | pages = [https://archive.org/details/handbookofattach0000unse_n9k8/page/41–105 }}</ref> Young himself was influenced by the work of the philosopher [[Kenneth Craik]].

==Neurobiology of attachment==
In addition to longitudinal studies, there has been [[Psychophysiology|psychophysiological]] research on the neurobiology of attachment.<ref name="foxhane">{{cite encyclopedia |year=2008 |title=Studying the Biology of Human Attachment |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York and London |pages=811–29 |isbn=978-1-59385-874-2 |vauthors=Fox NA, Hane AA |veditors=Cassidy J, Shaver PR}}</ref> Research has begun to include [[neural development]],<ref>{{cite journal | vauthors = Landers MS, Sullivan RM | title = The development and neurobiology of infant attachment and fear | journal = Developmental Neuroscience | volume = 34 | issue = 2–3 | pages = 101–14 | date = 2012 | pmid = 22571921 | pmc = 3593124 | doi = 10.1159/000336732 }}</ref> [[behaviour genetics]] and [[temperament]] concepts.<ref name= vbv/> Generally, temperament and attachment constitute separate developmental domains, but aspects of both contribute to a range of interpersonal and intrapersonal developmental outcomes.<ref name="vbv">{{cite encyclopedia |year=2008 |title=Attachment and Temperament |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York and London |pages=192–216 |isbn=978-1-59385-874-2 |vauthors=Vaughn BE, Bost KK, van IJzendoorn MH |veditors=Cassidy J, Shaver PR}}</ref> Some types of temperament may make some individuals susceptible to the stress of unpredictable or hostile relationships with caregivers in the early years.<ref name="marshall2005">{{cite journal |vauthors=Marshall PJ, Fox NA |year=2005 |title=Relationship between behavioral reactivity at 4 months and attachment classification at 14 months in a selected sample |journal=Infant Behavior and Development |volume=28 |issue=4 |pages=492–502 |doi=10.1016/j.infbeh.2005.06.002}}</ref> In the absence of available and responsive caregivers it appears that some children are particularly vulnerable to developing attachment disorders.{{sfn|Prior|Glaser|2006|p=219}}

Social background factors affect the quality of caregiving received at infancy and childhood and can thus correlate with variations in an individual's neurological systems which controls stress regulation.<ref name=foxhane/> In psychophysiological research on attachment, the two main areas studied have been [[Autonomic nervous system|autonomic response]]s, such as heart rate or respiration, and the activity of the [[hypothalamic–pituitary–adrenal axis]], a system that is responsible for the body's reaction to [[stress (biology)|stress]].<ref>{{cite book | vauthors = Adam EK, Klimes-Dougan B, Gunnar MR | chapter = Social regulation of the adrenocortical response to stress in infants, children, and adolescents. | veditors = Coch D, Dawson G, Fischer KW | title = Human behavior and the developing brain: Atypical development. | location = New York, NY | publisher = Guilford Press | date = 2007 | pages = 264–304 }}</ref> Infants' physiological responses have been measured during the Strange Situation procedure looking at individual differences in five simple social behaviours. Some recent studies suggest that early attachment relationships become molecularly instilled into a child's cells, thus affecting later immune system functioning.<ref name="Cassidy, Jude 2013">{{cite journal | vauthors = Cassidy J, Jones JD, Shaver PR | title = Contributions of attachment theory and research: a framework for future research, translation, and policy | journal = Development and Psychopathology | volume = 25 | issue = 4 Pt 2 | pages = 1415–34 | date = November 2013 | pmid = 24342848 | pmc = 4085672 | doi = 10.1017/s0954579413000692 }}</ref> Some studies suggest that early negative experiences (not necessarily attachment-relevant) affect the immune system in ways which may raise the chances of suffering from cardiovascular disease, autoimmune diseases, and certain types of cancer.<ref>{{cite journal | vauthors = Chung HY, Cesari M, Anton S, Marzetti E, Giovannini S, Seo AY, Carter C, Yu BP, Leeuwenburgh C | title = Molecular inflammation: underpinnings of aging and age-related diseases | journal = Ageing Research Reviews | volume = 8 | issue = 1 | pages = 18–30 | date = January 2009 | pmid = 18692159 | pmc = 3782993 | doi = 10.1016/j.arr.2008.07.002 }}</ref>

Advances in identifying key brain structures, neural circuits, neurotransmitter systems, and neuropeptides, open up the possibility of discovering how neurology might be involved in attachment system functioning (internal working models), if this could be operationally defined, and can indicate more about a certain individual.<ref>{{cite book | vauthors = Coan JA | chapter = Toward a neuroscience of attachment. | veditors = Cassidy J, Shaver PR | title = Handbook of attachment: Theory, research, and clinical applications. | url = https://archive.org/details/handbookofattach0000unse_n9k8 | edition = 2nd | location = New York, NY | publisher = Guilford Press | date = 2008 | pages = [https://archive.org/details/handbookofattach0000unse_n9k8/page/241 241]–265 }}</ref> There is initial evidence that caregiving and attachment involve both unique and overlapping brain regions.<ref>{{cite journal | vauthors = Bartels A, Zeki S | title = The neural correlates of maternal and romantic love | journal = NeuroImage | volume = 21 | issue = 3 | pages = 1155–66 | date = March 2004 | pmid = 15006682 | doi = 10.1016/j.neuroimage.2003.11.003 }}</ref> Another issue is the role of inherited genetic factors in shaping attachments: for example one type of [[Polymorphism (biology)#Genetic polymorphism|polymorphism]] of the gene coding for the [[Dopamine receptor D2|D<sub>2</sub>]] [[dopamine receptor]] has been linked to anxious attachment and another in the gene for the [[5-HT2A receptor|5-HT<sub>2A</sub>]] [[serotonin receptor]] with avoidant attachment.<ref>{{cite journal|author1-link=Omri Gillath | vauthors = Gillath O, Shaver PR, Baek JM, Chun DS | title = Genetic correlates of adult attachment style |url=https://archive.org/details/sim_personality-and-social-psychology-bulletin_2008-10_34_10/page/1396 | journal = Personality & Social Psychology Bulletin | volume = 34 | issue = 10 | pages = 1396–405 | date = October 2008 | pmid = 18687882 | doi = 10.1177/0146167208321484 }}</ref>

Studies show that attachment in adulthood is simultaneously related to biomarkers of immunity. For example, individuals with an avoidance attachment style produce higher levels of the pro inflammatory cytokine interleukin-6 (IL-6) when reacting to an interpersonal stressor,<ref>{{cite journal | vauthors = Gouin JP, Glaser R, Loving TJ, Malarkey WB, Stowell J, Houts C, Kiecolt-Glaser JK | title = Attachment avoidance predicts inflammatory responses to marital conflict | journal = Brain, Behavior, and Immunity | volume = 23 | issue = 7 | pages = 898–904 | date = October 2009 | pmid = 18952163 | pmc = 2771542 | doi = 10.1016/j.bbi.2008.09.016 }}</ref> while individuals representing an anxious attachment style tend to have elevated cortisol production and lower numbers of T cells.<ref>{{cite journal |last1=Jaremka |first1=Lisa M. |last2=Glaser |first2=Ronald |last3=Loving |first3=Timothy J. |last4=Malarkey |first4=William B. |last5=Stowell |first5=Jeffrey R. |last6=Kiecolt-Glaser |first6=Janice K. |title=Attachment Anxiety Is Linked to Alterations in Cortisol Production and Cellular Immunity |journal=Psychological Science |date=March 2013 |volume=24 |issue=3 |pages=272–279 |doi=10.1177/0956797612452571 |pmid=23307944 }}</ref> Although children vary genetically and each individual requires different attachment relationships, there is consistent evidence that maternal warmth during infancy and childhood creates a safe haven for individuals resulting in superior immune system functioning.<ref>{{cite journal | vauthors = Chen E, Miller GE, Kobor MS, Cole SW | title = Maternal warmth buffers the effects of low early-life socioeconomic status on pro-inflammatory signaling in adulthood | journal = Molecular Psychiatry | volume = 16 | issue = 7 | pages = 729–37 | date = July 2011 | pmid = 20479762 | pmc = 2925055 | doi = 10.1038/mp.2010.53 }}</ref> One theoretical basis for this is that it makes biological sense for children to vary in their susceptibility to rearing influence.<ref>{{cite encyclopedia |year=2008 |title=Precursors of Attachment Security |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York and London |pages=295–316 |isbn=978-1-59385-874-2 |vauthors=Belsky J, Pasco Fearon RM |veditors=Cassidy J, Shaver PR}}</ref>

The most recent and comprehensive neurobiological framework is the functional neuro-anatomical model of human attachment (NAMA) developed by Pascal Vrticka and colleagues,<ref>{{cite journal |last1=Long |first1=Madison |last2=Verbeke |first2=Willem |last3=Ein-Dor |first3=Tsachi |last4=Vrtička |first4=Pascal |title=A functional neuro-anatomical model of human attachment (NAMA): Insights from first- and second-person social neuroscience |journal=Cortex |date=May 2020 |volume=126 |pages=281–321 |doi=10.1016/j.cortex.2020.01.010 |pmid=32092496 }}</ref> which has been further extended to also include considerations of disorganised / disrupted attachment (NAMDA).<ref>{{cite journal |last1=White |first1=Lars O. |last2=Schulz |first2=Charlotte C. |last3=Schoett |first3=Margerete J. S. |last4=Kungl |first4=Melanie T. |last5=Keil |first5=Jan |last6=Borelli |first6=Jessica L. |last7=Vrtička |first7=Pascal |title=Conceptual Analysis: A Social Neuroscience Approach to Interpersonal Interaction in the Context of Disruption and Disorganization of Attachment (NAMDA) |journal=Frontiers in Psychiatry |date=23 December 2020 |volume=11 |article-number=517372 |doi=10.3389/fpsyt.2020.517372 |doi-access=free }}</ref> A narrative on the neurobiological roots of attachment-system functioning delineating the involved neurobiological circuits in more detail is also available.<ref>{{cite journal |last1=Izaki |first1=Amir |last2=Verbeke |first2=Willem J. M. I. |last3=Vrticka |first3=Pascal |last4=Ein-Dor |first4=Tsachi |title=A narrative on the neurobiological roots of attachment-system functioning |journal=Communications Psychology |date=16 October 2024 |volume=2 |issue=1 |article-number=96 |doi=10.1038/s44271-024-00147-9 |pmid=39406946 |pmc=11480372 }}</ref> The latest considerations of human attachment from a social neuroscience perspective furthermore emphasise the importance of bio-behavioural and interpersonal neural synchrony, which are summarised under the umbrella of relational neuroscience.<ref>{{cite journal |last1=De Felice |first1=Sara |last2=Chand |first2=Tara |last3=Croy |first3=Ilona |last4=Engert |first4=Veronika |last5=Goldstein |first5=Pavel |last6=Holroyd |first6=Clay B. |last7=Kirsch |first7=Peter |last8=Krach |first8=Sören |last9=Ma |first9=Yina |last10=Scheele |first10=Dirk |last11=Schurz |first11=Matthias |last12=Schweinberger |first12=Stefan R. |last13=Hoehl |first13=Stefanie |last14=Vrticka |first14=Pascal |title=Relational neuroscience: Insights from hyperscanning research |journal=Neuroscience & Biobehavioral Reviews |date=February 2025 |volume=169 |article-number=105979 |doi=10.1016/j.neubiorev.2024.105979 |pmid=39674533 }}</ref>

== Crime ==
Attachment theory has often been applied in the discipline of [[criminology]].<ref>{{cite journal |last1=Ranu |first1=Jasmin |last2=Kalebic |first2=Natasha |last3=Melendez-Torres |first3=G. J. |last4=Taylor |first4=Pamela J. |title=Association Between Adverse Childhood Experiences and a Combination of Psychosis and Violence Among Adults: A Systematic Review and Meta-Analysis |journal=Trauma, Violence, & Abuse |date=December 2023 |volume=24 |issue=5 |pages=2997–3013 |doi=10.1177/15248380221122818 |pmid=36117458 }}</ref> It has been used in an attempt to identify causal mechanisms in criminal behaviour – with uses ranging from [[offender profiling]], better understanding types of offence and the pursuit of preventative policy. It has been found that disturbances early on in child-caregiver relationships are a risk factor in criminality. Attachment theory in this context has been described as "perhaps the most influential of contemporary psychoanalytically oriented theories of crime".<ref>{{cite book |title=Psychology and Crime: An Introduction to Criminological Psychology |last=Hollin |first=Clive R. |publisher=Routledge |year=2013 |location=USA & Canada |page=62}}{{isbn?}}</ref>

=== Age distribution of crime ===
Two theories about why the crime peaks around the late teenage years and early twenties are called the developmental theory and life-course theory, and both involve attachment theory. Developmental perspectives argue that individuals who have disrupted childhood attachments will have criminal careers that continue long into adulthood.<ref name=":4">{{cite journal | vauthors = Moffitt TE, Caspi A | title = Childhood predictors differentiate life-course persistent and adolescence-limited antisocial pathways among males and females | url = https://archive.org/details/sim_development-and-psychopathology_spring-2001_13_2/page/355 | journal = Development and Psychopathology | volume = 13 | issue = 2 | pages = 355–75 | date = 2001 | pmid = 11393651 | doi = 10.1017/S0954579401002097 }}</ref> [[Life course approach|Life course perspectives]] argue that relationships at every stage of the life course can influence an individual's likelihood of committing crimes.<ref name=":5">{{cite journal |vauthors=Sampson RJ, Laub JH |date=2005 |title=A Life-Course View of the Development of Crime |journal=Annals of the American Academy of Political and Social Science |volume=602 |pages=12–45 |doi=10.1177/0002716205280075 }}</ref>

=== Types of offences ===
Disrupted attachment patterns from childhood have been identified as a risk factor for domestic violence.<ref name=":6">{{cite web | vauthors = Gilchrist E, Johnson R, Takriti R, Weston S, Anthony Beech A, Kebbell M | url = http://rds.homeoffice.gov.uk/rds/pdfs2/r217.pdf | archive-url = http://webarchive.nationalarchives.gov.uk/20110218141158/http://rds.homeoffice.gov.uk/rds/pdfs2/r217.pdf | archive-date = 2011-02-18 | title = Domestic Violence offenders: characteristics and offending related needs | date = 2003 | work = Research, Development and Statistics Directorate | publisher = United Kingdom Home Office | access-date = 2019-03-29 }}</ref> These disruptions in childhood can prevent the formation of a secure attachment relationship, and in turn adversely affecting a healthy way to deal with stress.<ref name=":7">{{cite journal |last1=Kesner |first1=John E. |last2=Julian |first2=Teresa |last3=McKenry |first3=Patrick C. |date=1997-06-01 |title=Application of Attachment Theory to Male Violence Toward Female Intimates |url=https://archive.org/details/sim_journal-of-family-violence_1997-06_12_2/page/211 |journal=Journal of Family Violence |volume=12 |issue=2 |pages=211–228 |doi=10.1023/A:1022840812546 }}</ref> In adulthood, lack of coping mechanisms can result in violent behaviour.<ref>{{cite book |title=Frustration and aggression |url=https://archive.org/details/frustrationaggre00doll |last1=Dollard |first1=John |last2=Miller |first2=Neal E. |last3=Doob |first3=Leonard W. |last4=Mowrer |first4=O. H. |last5=Sears |first5=Robert R. |date=1939 |publisher=Yale University Press |location=New Haven |doi=10.1037/10022-000}}</ref> Bowlby's theory of functional anger states that children signal to their caregiver that their attachment needs are not being met by use of angry behaviour. This perception of low support from partner has been identified as a strong predictor of male violence. Other predictors have been named as perceived deficiency in maternal love in childhood, low self-esteem.<ref name=":7" /> It has also been found that individuals with a dismissive attachment style, often seen in an antisocial/narcissistic-narcissistic subtype of offender, tend to be emotionally abusive as well as violent. Individuals in the borderline/emotionally dependent subtype have traits which originate from insecure attachment in childhood, and tend to have high levels of anger.<ref name=":6" />

It has been found that sexual offenders have significantly less secure maternal and paternal attachments compared with non-offenders which suggests that insecure attachments in infancy persist into adulthood.<ref>{{cite journal |last1=Smallbone |first1=Stephen W. |last2=Dadds |first2=Mark R. |title=Childhood Attachment and Adult Attachment in Incarcerated Adult Male Sex Offenders |journal=Journal of Interpersonal Violence |date=October 1998 |volume=13 |issue=5 |pages=555–573 |doi=10.1177/088626098013005001 }}</ref> In a recent study, 57% of sexual offenders were found to be of a preoccupied attachment style.<ref>{{cite book |title=What Works in Therapeutic Prisons | vauthors = Brown J, Miller S, Northey S, O'Neill D |publisher=Palgrave Macmillan |year=2014 |isbn=978-1-137-30620-3 |location=London |chapter=Attachments: The Multiple Sorting Task Procedure |doi=10.1057/9781137306210}}</ref> There is also evidence that suggests subtypes of sexual crime can have different attachment styles. Dismissive individuals tend to be hostile towards others, and are more likely to offend violently against adult women. By contrast, child abusers are more likely to have preoccupied attachment styles as the tendency to seek approval from others becomes distorted and attachment relationships become sexualized.<ref>{{cite journal | vauthors = Ward T, Beech A |date=2006 |title=An integrated theory of sexual offending |journal=Aggression and Violent Behavior |volume=11 |pages=44–63 |doi=10.1016/j.avb.2005.05.002}}</ref>

=== Uses within probation practice ===
Attachment theory has been of special interest within probation settings. When put into practice, probation officers aim to learn their probationer's attachment history because it can give them insight into how the probationer will respond to different scenarios and when they are the most vulnerable to reoffend. One of the primary strategies of implementation is to set up the probation officer as a secure base. This secure base relationship is formed by the probation officer being reliable, safe, and in tune with the probationer, and is intended to help give them a partly representational secure relationship that they have not been able to form.<ref>{{Cite web |last=Ansbro |first=Maria |date=September 2022 |title=Using attachment theory in probation practice |url=https://www.justiceinspectorates.gov.uk/hmiprobation/wp-content/uploads/sites/5/2022/09/v2.0-Academic-Insights-Ansbro-Sep-22.pdf |access-date=17 April 2024 |website=justiceinspectorates.gov.uk}}</ref>

==Practical applications==
As a theory of [[Developmental psychology|socioemotional development]], attachment theory has proved to have practical applications in social policy, in decisions about the care and welfare of children and about mental health. Attachment theory research also highlights that insecure attachment styles are linked to difficulties in emotional regulation and the development of maladaptive coping strategies, which can have long-term implications for mental health treatment planning.<ref name="Mikulincer2019">Mikulincer, Mario; Shaver, Phillip R. (2019). Attachment in Adulthood: Structure, Dynamics, and Change. Guilford Press.</ref>

=== Child care policies ===
Social policies concerning the care of children were the driving force in Bowlby's development of attachment theory. The difficulty lies in applying attachment concepts to policy and practice.<ref name="rut08">{{cite encyclopedia |year=2008 |title=Implications of Attachment Theory and Research for Child Care Policies |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York and London |pages=[https://archive.org/details/handbookofattach0000unse_n9k8/page/958 958–74] |isbn=978-1-60623-028-2 | vauthors = Rutter M |veditors=Cassidy J, Shaver PR |url= https://archive.org/details/handbookofattach0000unse_n9k8/page/958 }}</ref> In 2008 [[C.H. Zeanah]] and colleagues stated, "Supporting early child-parent relationships is an increasingly prominent goal of mental health practitioners, community-based service providers and policy makers&nbsp;... Attachment theory and research have generated important findings concerning early child development and spurred the creation of programs to support early child-parent relationships."<ref name="BZL">{{cite encyclopedia |year=2008 |title=Prevention and Intervention Programs for Supporting Early Attachment Security |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York and London |pages=[https://archive.org/details/handbookofattach0000unse_n9k8/page/745 745–61] |isbn=978-1-60623-028-2 |vauthors=Berlin L, Zeanah CH, Lieberman AF |veditors=Cassidy J, Shaver PR |url=https://archive.org/details/handbookofattach0000unse_n9k8/page/745 }}</ref> Thus the [[NICHD]] has in the past held that the mark of top notch day care is that it contributes to secure attachment relationships in children.<ref>{{cite journal | author = NICHD Early Child Care Research Network | year = 1997 | title = The effects of infant child care on infant-mother attachment security: Results of the NICHD study of early child care | url = https://archive.org/details/sim_child-development_1997-10_68_5/page/860 | journal = Child Development | volume = 68 | issue = 5| pages = 860–879 | doi = 10.2307/1132038 | jstor = 1132038 }}</ref> 

However, child care policy is highly contested and it has recently been shown that making the maintenance of infant-caregiver bonds the primary index of good-quality child care does not gel well with the group-based environment of most Western forms of [[early childhood education]] and care. The difficulties of one key-worker maintaining availability, sensitivity and appropriate one-to-one responsiveness to several children at the same time, the frequency of part-time work in child care facilities and high staff-turnover means the imperative to build secure one-to-one infant-caregiver attachments is well-nigh impossible to achieve, putting undue stress on both infants and educators.<ref>{{Cite journal |last1=Chamberlain |first1=Michaela |date=2025 |title= Babies in Groups: A Review |journal= British Journal of Psychotherapy | volume=41 | pages=589–591 |doi=10.1111/bjp.12959 }}</ref> Hence, recently, group-based care, as occurs in Japan, has been argued to be more in keeping with high quality child care than NICHD-like imperatives to maintain one-to-one care encouraged by attachment advocates.<ref>{{cite book |title=The Myth of Attachment Theory: A Critical Understanding for Multicultural Societies |publisher=Routledge |location=London |year=2021 |isbn= 978-1-00-316709-9 |author-last1=Keller |author-first1=Heidi }}{{pn|date=November 2025}}</ref> All the same, and despite the many empirical, cross-cultural and methodological critiques of attachment theory, some policy-makers continue energetically to advocate the view that "legislative initiatives reflecting higher standards for credentialing and licensing childcare workers" require "education in child development and attachment theory, and at least a two-year associate degree course as well as salary increases and increased stature for childcare positions".<ref name="Sweeney GM 2007. pp. 332">{{cite book | vauthors = Sweeney GM | chapter = Why childhood attachment matters: Implications for personal happiness, families and public policy. | veditors = Loveless S, Homan T | title = The family in the new millennium. | url = https://archive.org/details/familyinnewmille0000unse | location = Westport, CT | publisher = Praeger | date = 2007 | pages = [https://archive.org/details/familyinnewmille0000unse/page/332 332]–346 }}</ref> 

Arguments for more flexible work arrangements that recognize child care as essential for all its employees also sometimes reference attachment theory. This includes re-examination of parental leave policies, the main idea being that lack of parental leave inhibits early parent child bonding.<ref name="Cassidy, Jude 2013" /> 

In the past, attachment theory has often been held to have had significant policy implications for hospitalized or institutionalized children, and those in poor quality daycare.{{sfn|Karen|1998|pp=252–58}} Nowadays, historians challenge this belief: attachment theory being just part of a far wider movement towards child-centredness.<ref>{{Cite journal |last1=Van der Horst |first1=Frank |last2=van der Veer|first2= René |date=2009 |title= Changing Attitudes towards the Care of Children in Hospital: A New Assessment of the Influence of the Work of Bowlby and Robertson in the UK, 1940– 1970|journal= Attachment & Human Development | volume=11 |issue=2 | pages=119–142 |doi=10.1080/14616730802503655 |pmid=19266362 }}</ref> 

Ideological investment in the belief that babies are best raised by home-alone mothers leads some attachment advocates to maintain that non-maternal care, particularly in group settings, has deleterious effects on social development. This view is not supported by rigorous research, though it is plain that poor quality care carries risks while young children who experience good quality out-of-home care typically flourish when a group-based approach is taken to care in group settings.<ref>{{Cite journal |last1=Chamberlain |first1=Michaela |date=2025 |title= Babies in Groups: A Review |journal= British Journal of Psychotherapy | volume=41 | pages=589–591 |doi=10.1111/bjp.12959 }}</ref><ref name=rut08/>

Attachment theory has mixed implications in [[Family law|residence]] and [[Contact (law)|contact]] disputes,{{sfn|Karen|1998|pp=252–58}} and applications by foster parents to adopt foster children. In the past, particularly in North America, the main theoretical framework was psychoanalysis. Increasingly attachment theory has replaced it, thus focusing on the quality and continuity of caregiver relationships rather than economic well-being or automatic precedence of any one party, such as the biological mother. [[Michael Rutter|Rutter]] noted that in the UK, since 1980, family courts have shifted considerably to recognize the complications of attachment relationships.<ref name="rut99">{{cite encyclopedia |year=1999 |title=Implications of Attachment Theory for Child Care Policies |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York |url=https://archive.org/details/handbookofattach0000unse/page/823 |pages=[https://archive.org/details/handbookofattach0000unse/page/823 823–44] |isbn=978-1-57230-087-3 |vauthors=Rutter M, O'Connor TG |veditors=Cassidy J, Shaver PR}}</ref> Children tend to have attachment relationships with both parents and often grandparents or other relatives. While, through an attachment prism, judgements have been deemed to need to take this into account along with the impact of step-families, new evidence refutes this. In consequence, Britain's Ministry of Justice has ruled that family law judgements will not longer assume that being in contact with both parents is in the best interests of the child.<ref>{{Cite journal |last1=Campbell |first1=Adina |date=2025 |title= Family court law on parental contact for children to change |journal= BBC News | url=https://www.bbc.co.uk/news/articles/cx2lxgp58j5o }}</ref>

Attachment theory can also inform decisions made in [[social work]], especially in [[Humanistic psychology|humanistic social work]] ([[Microsociology|Petru Stefaroi]]),<ref name="Stefaroi">{{cite journal |id={{CEEOL|275722}} {{ProQuest|956750207}} |last1=Stefăroi |first1=Petru |title=Paradigma umanistă a asistenţei sociale sau scurtă introducere în asistenţa socială umanistă |trans-title=Humanistic Paradigm of Social Work or Brief Introduction in Humanistic Social Work |journal=Revista de Asistenţă Socială |date=2012 |issue=1 |pages=161–174 }}</ref><ref name="Stefaroi P.">{{cite book | vauthors = Stefaroi P | date = 2014 | title = Humane & Spiritual Qualities of the Professional in Humanistic Social Work: Humanistic Social Work – The Third Way in Theory and Practice | location = Charleston, SC | publisher = Createspace }}</ref> and court processes about [[foster care]] or other placements. The Westernised assumptions built into attachment theory about family-structure and the gendered division of labour sometimes make these decisions profoundly unethical.<ref>{{cite book |title=The Myth of Attachment Theory: A Critical Understanding for Multicultural Societies |publisher=Routledge |location=London |year=2021 |isbn= 978-1-00-316709-9 |author-last1=Keller |author-first1=Heidi  }}</ref> Nevertheless, considering the child's attachment needs often determines the supposed level of risk posed by placement options.<ref name="0to3">{{cite journal |last1=Goldsmith |first1=Douglas F. |last2=Oppenheim |first2=David |last3=Wanlass |first3=Janine |title=Separation and Reunification: Using Attachment Theory and Research to Inform Decisions Affecting the Placements of Children in Foster Care |journal=Juvenile and Family Court Journal |date=April 2004 |volume=55 |issue=2 |pages=1–13 |doi=10.1111/j.1755-6988.2004.tb00156.x }}</ref><ref>{{cite journal | vauthors = Crittenden PM, Farnfield S, Landini A, Grey B |year=2013 |title=Assessing attachment for family court decision making |journal=Journal of Forensic Practice |volume=15 |issue=4 |pages=237–248 |doi=10.1108/jfp-08-2012-0002 }}</ref>

=== Clinical practice with children ===
Despite criticism, attachment theory remains a high-profile theory of [[Developmental psychology|socioemotional development]] with a scientific reputation and it continues to generate a lot of research. Yet it has, until recently, been less used in clinical practice.<ref>{{cite journal |last1=Cassidy |first1=Jude |last2=Jones |first2=Jason D. |last3=Shaver |first3=Phillip R. |title=Contributions of attachment theory and research: A framework for future research, translation, and policy |journal=Development and Psychopathology |date=November 2013 |volume=25 |issue=4pt2 |pages=1415–1434 |doi=10.1017/S0954579413000692 |pmid=24342848 |pmc=4085672 }}</ref> This may be partly due to lack of attention paid to clinical application by Bowlby himself and partly due to broader meanings of the word 'attachment' used among practitioners. It may also be partly due to the mistaken association of attachment theory with the [[pseudoscience|pseudoscientific]] interventions misleadingly known as [[attachment therapy]] or holding therapy.<ref name="Ziv">{{cite encyclopedia |year=2005 |title=Attachment-Based Intervention programs: Implications for Attachment Theory and Research |encyclopedia=Enhancing Early Attachments: Theory, Research, Intervention and Policy |publisher=Guilford Press |location=New York and London |series=Duke series in child development and public policy |page=63 |isbn=978-1-59385-470-6 | vauthors = Ziv Y |veditors=Berlin LJ, Ziv Y, Amaya-Jackson L, Greenberg MT}}</ref> But it is most likely the result of the narrowness of the assumptions about family-life built into attachment theory.<ref >{{cite book |title= The Cultural Nature of Attachment: Contextualizing Relationships and Development |publisher=MIT Press |location=Cambridge |year=2017 |isbn= 978-0-262-03690-0 |editor-last1=Keller |editor-first1=Heidi |editor-last2=Bard |editor-first2=Kim }}{{pn|date=November 2025}}</ref><ref>{{cite book |title=The Myth of Attachment Theory: A Critical Understanding for Multicultural Societies |publisher=Routledge |location=London |year=2021 |isbn= 978-1-00-316709-9 |author-last1=Keller |author-first1=Heidi  }}{{pn|date=November 2025}}</ref>

=== Attachment-based therapy ===
{{Main|Attachment-based therapy}}

In 1988, Bowlby published a series of lectures indicating how attachment theory and research could be used in understanding and treating child and family disorders. His focus for bringing about change was the parents' internal working models, parenting behaviours and the parents' relationship with the therapeutic intervenor.<ref name="berlinetal">{{cite encyclopedia |year=2008 |title=Prevention and Intervention Programs for Supporting Early Attachment Security |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York and London |pages=745–61 |isbn=978-1-59385-874-2 |vauthors=Berlin LJ, Zeanah CH, Lieberman AF |veditors=Cassidy J, Shaver PR}}</ref> Ongoing research has led to a number of individual treatments and prevention and intervention programs.<ref name=berlinetal/> In regards to personal development, children from all the age groups were tested to show the effectiveness of the theory that is being theorized by Bowlby. They range from individual therapy to public health programs to interventions designed for foster caregivers. For infants and younger children, the focus is on increasing the responsiveness and sensitivity of the caregiver, or if that is not possible, placing the child with a different caregiver.{{sfn|Prior|Glaser|2006|pp=231–32}}<ref name="BakermansKranenburg">{{cite journal | vauthors = Bakermans-Kranenburg MJ, van IJzendoorn MH, Juffer F | title = Less is more: meta-analyses of sensitivity and attachment interventions in early childhood | url = https://archive.org/details/sim_psychological-bulletin_2003-03_129_2/page/195 | journal = Psychological Bulletin | volume = 129 | issue = 2 | pages = 195–215 | date = March 2003 | pmid = 12696839 | doi = 10.1037/0033-2909.129.2.195 }}</ref> An assessment of the attachment status or caregiving responses of the caregiver is invariably included, as attachment is a two-way process involving attachment behaviour and caregiver response. Some programs are aimed at foster cares because the attachment behaviours of infants or children with attachment difficulties often do not elicit appropriate caregiver responses. Modern prevention and intervention programs have proven successful.<ref>{{cite journal | vauthors = Hoffman KT, Marvin RS, Cooper G, Powell B | title = Changing toddlers' and preschoolers' attachment classifications: the Circle of Security intervention | url = https://archive.org/details/sim_journal-of-consulting-and-clinical-psychology_2006-12_74_6/page/1017 | journal = Journal of Consulting and Clinical Psychology | volume = 74 | issue = 6 | pages = 1017–26 | date = December 2006 | pmid = 17154732 | doi = 10.1037/0022-006x.74.6.1017 }}</ref>

In the view of attachment-based therapists attachment theory offers a broad, far-reaching view of human functioning, and can enrich a therapist's understanding of patients and the therapeutic relationship rather than dictate a particular form of treatment.<ref name="Slade 2008">{{cite encyclopedia |year=2008 |title=Attachment Theory and Research: Implications for the theory and practice of individual psychotherapy with adults |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications |publisher=Guilford Press |location=New York and London |pages=762–82 |isbn=978-1-59385-874-2 | vauthors = Slade A |veditors=Cassidy J, Shaver PR}}</ref> Some forms of [[Attachment-based psychotherapy|psychoanalysis-based therapy]] for adults—within [[relational psychoanalysis]] and other approaches—also incorporate attachment theory and patterns.<ref name="Slade 2008" /><ref name="Sable">{{cite book |title=Attachment & Adult Psychotherapy | vauthors = Sable P |publisher=Aaronson |year=2000 |isbn=978-0-7657-0284-5 |location=Northvale, NJ}}</ref>

==Criticism==
John Bowlby staunchly defended attachment theory as being a theory of the kind [[Karl Popper]] called scientific.<ref>{{cite journal | vauthors =Bowlby J|year=1982 |title= A Case of Mistaken Identity |journal=Higher Education Quarterly |volume=36 |issue=4 |pages=328–332 |doi=10.1111/j.1468-2273.1982.tb01342.x }}</ref> This meant it would be refuted if any of its empirical predictions were found to be false. Mary Ainsworth and her colleagues disagreed:
{{blockquote| Attachment theory might be described as "programmatic" and open-ended. It does not purport to be a tight network of propositions on the basis of which hypotheses may be formulated, any one of which, in the event of an adequate but unsuccessful test, could invalidate the theory as a whole ... Despite its lack of resemblance to a mathematico-physical theory, both the general theory of behaviour and attachment theory amount to what Kuhn (1962) termed a paradigm change for developmental psychology—a complete shift of perspective.<ref>{{cite book | vauthors = Ainsworth MD, Blehar M, Waters E, Wall S | date = 2015 | title = Patterns of Attachment: A Psychological Study of the Strange Situation | location = New York | publisher = Psychology Press| pages = 4| isbn = 9781848726826 }}</ref>}}
Many of Bowlby's empirical claims and predictions ''have'' been refuted by subsequent research, yet the latest edition of ''The Handbook of Attachment'' asserts that "nothing that has emerged from the thousands of studies produced over the past 40 years has led to a serious challenge to the core theory ... since the time of Bowlby's writings."<ref name="Cassidy">{{cite encyclopedia |year=2016 |title=The Nature of a Child's Ties |encyclopedia=Handbook of Attachment: Theory, Research and Clinical Applications 3rd edition|publisher=Guilford Press |location=New York | veditors = Cassidy J, Shaver PR |pages=[https://archive.org/details/handbookofattach0000unse/page/17 3–24] |isbn=978-1-4625-2529-4 }}</ref> This supports Ainsworth's contention that attachment theory is ''not'' a scientific theory but a psycho-social movement of the kind identified by [[Thomas Kuhn]] as lying ''behind'' changes of epistemic perspective. This does not stop many people, including attachment advocates, developmental psychologists and policy-makers, continue to claim that attachment theory ''is'' scientific. As [[developmental psychology |developmental psychologist]] Suzanne Zeedyk puts it, when attachment theory is referred to nowadays: "that statement is no longer regarded as 'theory'.  The operation of the attachment system is now regarded as 'fact.'"<ref >{{cite web| url=https://suzannezeedyk.com/attachment-suzanne-zeedyk/|last1=Zeedyk|first1= Suzanne |year=2016|title= Attachment (1st May 2016)|accessdate=Oct 23, 2025}}</ref>

=== The attachment theory bubble ===
The attachment perspective attracts tender-hearted scientists and layfolk alike because it is seen as putting children and their needs at centre stage of developmental discussions. Attachment advocates sometimes go further than this, writing as if [[parenting styles |child-centered parenting styles]] are a direct consequence of Bowlby's theory (though, in fact, child-centeredness [[The Common Sense Book of Baby and Child Care | was being popularized a decade or more before]] he devised his theory). The over-estimation of the importance of Bowlby's influence has become a staple of the attachment movement,<ref>{{Cite journal |last1=Van der Horst |first1=Frank |last2=van der Veer|first2= René |date=2009 |title= Changing Attitudes towards the Care of Children in Hospital: A New Assessment of the Influence of the Work of Bowlby and Robertson in the UK, 1940–1970 |journal= Attachment & Human Development | volume=11 |issue=2 | pages=119–142 |doi=10.1080/14616730802503655 |pmid=19266362 }}</ref> which often pays tribute to him as if he were a saint. Thus the prominent British psychoanalyst Professor Brett Kahr states that Bowlby's findings are now "beyond all doubt", and as a consequence:
{{blockquote| Bowlby's paradigm, now known as attachment theory, deserves a place in the history of medicine, in the history of psychology, in the history of science, and in the history of humanity, as one of the greatest achievements, on a par, I wish to suggest, with the art of Leonardo da Vinci, the music of Wolfgang Amadeus Mozart, and the nonviolent militarism of Mohandas Gandhi.<ref name="Kahr 2012">{{cite book |title= Shattered States: Disorganized Attachment and Its Repair |last1=Kahr |first1=Brett |publisher=Karnac Books |location=London |year=2012 |isbn= 978-1-85575-831-5 |editor-last1= Yellin |editor-first1=Judy |editor-last2=White |editor-first2=Kate |page=8 |chapter= The Infanticidal Origins of Psychosis: The Role of Trauma in Schizophrenia }}</ref>}}
Fulsome praise for high-profile attachment theorists is commonplace within attachment theory-promoting circles. Thus [[Peter Fonagy]] and his colleagues state that attachment theory is securely based on "the complex and meticulous observational work of Mary Ainsworth", and that the concept of ''internal working models'' has been sanctioned by some of the "greatest minds in the attachment field".<ref name="Fonagy 2016">{{cite book |title= Handbook of Attachment: Theory, Research and Clinical Applications |last1=Fonagy |first1=Peter | last2=Luyten |first2=Patrick | last3=Allison |first3=Elizabeth | last4=Campbell |first4=Chloe |publisher=Guildford Press |location=New York |year=2016 |isbn= 978-1-4625-2529-4 |editor-last1= Shaver |editor-first1=Jude |editor-last2=Shaver |editor-first2=Philip |pages=781 |chapter= Reconciling Psychoanalytic Ideas with Attachment Theory}}</ref>

The presence of a strong [[in-group and out-group]] dynamic within attachment advocacy is confirmed by the way that those 'inside the bubble' fail to see the theory's scientific short-comings until they remove themselves. Here is Judi Mesman's observation:
{{blockquote| Having been academically 'raised' in one of the world's strongholds of attachment research, I was a firm believer of the universality assumptions of attachment theory and its methods. It wasn't until I started working with young scholars from the Global South, collecting video data of family life in over 20 countries, that I could not escape questioning the basis for some of these universality claims.<ref name="Mesman 2021">{{cite book |title= Attachment: The Fundamental Questions |last1=Mesman |first1=Judi | publisher=Guildford Press |location=New York |year=2021 |isbn= 978-1-4625-4602-2 |editor-last1= Thompson |editor-first1=Ross |editor-last2=Simpson |editor-first2=Jeffrey |page=245 |chapter = Attachment Theory's Universality Claims: Asking Different Questions }}</ref>}}
Conversely, if scientists who work inside the attachment theory bubble publish results which ''do'' seriously challenge the claims of attachment theory, those results are typically ignored and the scientists themselves ostracised. For example, the findings and arguments that [[Michael Lamb]] and colleagues published  in the 1980s to challenge the attachment perspective are neither referenced nor discussed in the latest edition of ''The Handbook of Attachment'' (a book of 43 chapters),<ref>{{cite book | vauthors = Cassidy J, Shaver PR | title = Handbook of attachment: Theory, research, and clinical applications |isbn= 978-1-4625-2529-4 | edition = 3rd | location = New York, NY | publisher = Guilford Press | date = 2016 }}</ref><ref>{{cite journal | vauthors = Lamb M, Thompson R, Gardner W, Charnov E, Estes D | title = Security of Infantile Attachment as Assessed in the 'Strange Situation': Its Study and Biological Interpretation |journal = Behavioural and Brain Sciences | volume = 7 | pages = 127–147 | year = 1984 | doi = 10.1017/S0140525X00026522 }}</ref><ref>{{cite book  | vauthors = Lamb M, Thompson R, Gardner W, Charnov E, Cannon J | editor-first1 = Michael E. | editor-first2 = Ross A. | editor-first3 = William | editor-first4 = Eric L. | editor-last1 = Lamb | editor-last2 = Thompson | editor-last3 = Gardner | editor-last4 = Charnov | title = Infant–Mother Attachment: The Origins and Developmental Significance of Individual Differences in Strange Situation Behaviour |publisher=Erlbaum |place=Hillsdale NJ | year = 1985 | doi = 10.4324/9780203781791 | isbn = 978-1-134-92918-4 }}</ref> Lamb's attachment-advocating colleagues having "effectively ostracized" him. <ref>{{cite book |title= The Cultural Nature of Attachment: Contextualizing Relationships and Development |last1=Vicedo |first1=Marga |publisher=MIT Press |location=Cambridge |year=2017 |isbn= 978-0262036900 |editor-last1=Keller|editor-first1=Heidi |editor-last2=Bard |editor-first2=Kim | page=33 |chapter=The Strange Situation of the Ethological Theory of Attachment: A Historical Perspective}}</ref>

=== Faulty descriptive base ===
Bowlby's aim to replace psychoanalysts' phantasy-focused interpretive accounts of young children's hidden mental lives with the findings of [[ethology |direct observation]] as a grounding for his theory has had to be forsaken. Attachment theory has retreated from any serious grounding in a [[natural history]] of very young children and now champions the expert interpretation of a limited number of pre-defined behaviours in the [[Strange Situation |Strange Situation Procedure]] (SSP) as shedding light on invisible ''internal working models'' which have no generally-agreed definition.<ref name="Thompson 2017"/>

Particular observational claims made by Bowlby which are now refuted include studies showing that the ''attachment behaviours'' which he attributed to young infants are neither [[fixed action pattern |fixed in form]] nor insensitive to their context-of-use (as he claimed);<ref>Bowlby (1969) 2nd ed. p.65.</ref> nor do these behaviours exhaust babies' relationship-relevant social repertoire.<ref>{{cite journal |last1=Chamberlain |first1=Michaela |title=Babies in Groups: A Review |journal=British Journal of Psychotherapy |date=2025 |volume=41 |pages=589–593 |doi=10.1111/bjp.12959 }}</ref> Contrary to Bowlby's empirical claims, ''fear of strangers'' and ''separation anxiety'' are not normally observed when 'securely attached' infants or toddlers are left by their mothers with strangers.<ref>{{cite book | vauthors = Ainsworth MD, Blehar M, Waters E, Wall S | date = 2015 | title = Patterns of Attachment: A Psychological Study of the Strange Situation | location = New York | publisher = Psychology Press| pages = 262ff | isbn = 9781848726826 }}</ref> Attachment behaviours are ''not'' integrated over the first years of life into what ethologists call ''behavioural systems'' of which all the components should regularly appear in the same intercorrelated order.<ref>{{cite journal |last1=Waters |first1=Everett |title= The Reliability and Stability of Individual Differences in Infant– Mother Attachment | journal=Child Development | date=1978 |volume=49 |issue=2 |pages=483–494 |doi=10.2307/1128714 |jstor=1128714 }}</ref> 

Likewise, the observational research by Mary Ainsworth and her colleagues upon which the SSP was first based proves to have been far from "meticulous", contrary to the beliefs of attachment theorists.<ref name="Fonagy 2016">{{cite book |title= Handbook of Attachment: Theory, Research and Clinical Applications |last1=Fonagy |first1=Peter | last2=Luyten |first2=Patrick | last3=Allison |first3=Elizabeth | last4=Campbell |first4=Chloe |publisher=Guildford Press |location=New York |year=2016 |isbn= 978-1-4625-2529-4 |editor-last1= Shaver |editor-first1=Jude |editor-last2=Shaver |editor-first2=Philip |pages=781 |chapter= Reconciling Psychoanalytic Ideas with Attachment Theory}}</ref> Marga Vicedo, one of the few scholars to have inspected at first hand Ainsworth and her team's original observational records in the definitive study grounding the SSP, reports as follows:
{{blockquote| Although confidentiality prevents quoting directly from these data, the narrative reports from these observations that I have seen cannot be considered trustworthy scientific reports. Several of them are permeated with subjective evaluations of the mothers' personality from day one, including moral judgements. Other reports reveal tensions between the observer and the observed mothers. In addition, the reports from the different observers vary substantially in nature and quality, and most of them do not include notes taken every five minutes. In fact, one observer did not write up the observations until months later.<ref>{{cite book |title= The Cultural Nature of Attachment: Contextualizing Relationships and Development |last1=Vicedo |first1=Marga |publisher=MIT Press |location=Cambridge |year=2017 |isbn= 978-0262036900 |editor-last1=Keller|editor-first1=Heidi |editor-last2=Bard |editor-first2=Kim | pages=34 |chapter=The Strange Situation of the Ethological Theory of Attachment: A Historical Perspective}}</ref>}}

=== The Strange Situation is not a reliable procedure ===
When the reliability of the SSP is tested, results do not remain stable, especially when the backcloth of social circumstances of infant-adult couples changes between tests. Studies show that the greatest reliability is found in attachment ratings from the SSP when the social background of the infant's family remains stable between two assessments: socio-economically; maritally; in terms of social support; housing; and childcare provision. But the crucial test is when background variables change between tests. Then it is found that, as a baby's social background changes between two SSP ratings, the ratings are also likely to change. SSP classifications are especially volatile when researchers make the effort to recruit to their studies infants who do not come from intact middle-class families and whose parents have not volunteered to participate.<ref name="Lamb">{{cite journal |last1=Lamb |first1=Michael E. |last2=Thompson |first2=Ross A. |last3=Gardner |first3=William P. |last4=Charnov |first4=Eric L. |last5=Estes |first5=David |title=Security of infantile attachment as assessed in the 'strange situation': Its study and biological interpretation |journal=Behavioral and Brain Sciences |date=March 1984 |volume=7 |issue=1 |pages=127–147 |doi=10.1017/S0140525X00026522 }}</ref><ref name="Lamb 1985">{{cite book |editor-first1=Michael E. |editor-first2=Ross A. |editor-first3=William |editor-first4=Eric L. |editor-last1=Lamb |editor-last2=Thompson |editor-last3=Gardner |editor-last4=Charnov |title=Infant-Mother Attachment |date=2013 |doi=10.4324/9780203781791 |isbn=978-1-134-92918-4 }}{{pn|date=November 2025}}</ref><ref name="Booth LaForce 2021">{{cite book |title=Attachment: The Fundamental Questions |last1=Booth LaForce |first1=Cathryn |last2=Roisman |first2=Glenn |publisher=Guildford |location=New York |year=2021 |isbn= 978-1-4625-4602-2 |editor-last1= Thompson |editor-first1=Ross |editor-last2=Simpson |editor-first2=Jeffrey |editor-last3=Berlin |editor-first3=Lisa |pages=154–160 |chapter=Stability and Change in Attachment Security}}</ref><ref>{{cite journal |last1=De Wolff |first1=Marianne |last2=Van IJzendoorn |first2=Marinus |title= Sensitivity and Attachment: A Meta-Analysis on Parental Antecedents of Infant Attachment |journal=Child Development |date=1997 |volume=68 |issue=4 |pages=571–591 |doi=10.1111/j.1467-8624.1997.tb04218.x |pmid=9306636 }}</ref>

An important corollary of this finding is that attachment studies which ''do not'' [[Scientific control |control]] for a family's social background--and many do not--they may produce results which, for example, seem to prove levels of security in attachment classification have a strong positive [[Correlation does not imply causation |correlation]] with a factor like maternal sensitivity, when, in fact, levels of security and sensitivity are both caused by other unstudied factors from their social background. This means that the results of correlational studies which seem to prove the long-term effects of an infant's attachment classification cannot be taken at face-value if those studies were [[Scientific control |uncontrolled]]: the strength of correlations is likely to have been inflated by one or more of the unstudied background variables.

In short, classifications of attachment in/security derived from the SSP cannot be taken as primarily reflecting the existence of an ''internal'' system or working model in the young child. They are far more likely to be reflecting what has recently been happening in the social world ''external'' to the infant and her or his mother-figure(s) at the times of their assessment.

=== Attachment classifications of children seldom predict adult functioning ===
The best-known [[longitudinal study |longitudinal studies]] to have researched the long-term effects/correlates of infant-caregiver bonds on grown-up functions have all failed to produce the kinds of result attachment theory predicts. This is especially true in studies which have controlled for the continuity and discontinuity of background variables experienced by the child while she or he was developing.<ref>{{cite book |title=Attachment from Infancy to Adulthood: The Major Longitudinal Studies |publisher=Guildford |location=New York |year=2006 |isbn= 978-1-4625-4602-2 |editor-last1=Grossman |editor-first1=Klaus |editor-last2=Grossman |editor-first2=Karin |editor-last3=Waters |editor-first3=Everett }}</ref> One longitudinal study in Minnesota showed that, if background variables were properly taken into account, attachment security in infancy only accounted for 5% of the [[variance |variability]] in social competence when the study-children had reached the age of nineteen. Two well-known German studies also failed to find any significant correlation between security of attachment (as measure in the SSP) in toddlers and a variety of measures of social relating after age ten. Long-term Israeli research also found that continuity in attachment representation correlated strongly with the stability of the caregiver's environment, and discontinuity with instability. 

Taken altogether, such findings demonstrate that, when studies using SSP measures include measures of an infant's social circumstances, there can be a strong link to grown-up outcomes—accounting for ''half'' the [[variance]] in the 'Minnesota' longitudinal study when, by themselves, attachment measures account for as little as ''one twentieth'' of the variance .<ref>{{cite journal |last1=Rutter |first1=Michael |title=Critical Notice |journal=Journal of Child Psychology and Psychiatry |date=2006 |volume=47 |pages=974–977 |doi=10.1111/j.1469-7610.2006.01644.x }}</ref>

=== A flawed evolutionary rationale ===
From the beginning, attachment theory side-lined the essential role of caregivers behaviours in promoting child well-being, both in our Stone Age ancestors and in families today. It took the primary factor in promoting an infant's survival to be a biological provision in babies themselves. This provision has been variously called an ''instinct'', an ''attachment behavioural system'' and ''an internal working model''. Yet the theory ''also'' acknowledges that the baby's biological provision does not become operational until the baby is mobile, not being fully formed until after a child has reached its third birthday according to Bowlby. Which, if the theory were true, would make babies vulnerable to all sorts of peril for up to three years after birth. Tacitly, Bowlby and Ainsworth's strictures on maternal care make it plain that it is caregivers who guarantee very young children's safety and security, ''not'' a hypothesized attachment behavioural system or ''working model''.

Furthermore the evidential claims made by Bowlby to support his attribution of attachment behaviour to primates and to hunter-gatherers are not supported by empirical studies.

== See also ==
{{Portal|Psychology|Zoology}}
<!-- Please keep entries in alphabetical order & add a short description [[WP:SEEALSO]] -->
{{div col|colwidth=20em}}
*{{Annotated link|Atlas personality}}
*{{Annotated link|Attachment parenting}}
*{{Annotated link|Attachment theory and psychology of religion}}
*{{Annotated link|Fathers as attachment figures}}
*{{Annotated link|Human bonding}}
*{{Annotated link|Nurture kinship}}
*{{Annotated link|Parental love}}
*{{Annotated link|Passionate and companionate love}}
*{{Annotated link|Relationship science}}
{{div col end}}
<!-- please keep entries in alphabetical order -->
== Citations ==
{{Reflist}}

== General and cited references ==
{{refbegin}}
* {{cite book |last=Bowlby |first=J |title=Child Care and the Growth of Love |publisher=Penguin Books |year=1953 |isbn=978-0-14-020271-7 |location=London}}  Version of WHO publication ''Maternal Care and Mental Health'' published for sale to the general public.
* {{cite book |last=Bowlby |first=J |title=Attachment and Loss (Vol. 1: Attachment) |publisher=Penguin Books |year=1971 |isbn=978-0-14-021276-1 |edition=1st |location=London |orig-date=1969}}
* {{cite book |last=Bowlby |first=J |url=https://archive.org/details/makingbreakingof00bowl |title=The Making and Breaking of Affectional Bonds |publisher=Tavistock Publications |year=1979 |isbn=978-0-422-76860-3 |location=London}}
* {{cite book |last=Bowlby |first=J |title=Attachment and Loss (Vol. 1: Attachment) |publisher=Basic Books |year=1982 |isbn=978-0-465-00543-7 |edition=2nd |location=New York |lccn=00266879 |oclc=11442968 |id=NLM 8412414 }}
* {{cite book |last=Bowlby | first = J |title=Attachment |url=https://archive.org/details/attachmentloss00bowl |publisher=Basic Books |year=1999 |isbn=0-465-00543-8 |edition=2nd |series=Attachment and Loss Vol. I |location=New York |oclc=11442968 |id=NLM 8412414 |orig-date=1982|lccn=00266879 }}
* {{cite book |last=Craik |first=K |title=The Nature of Explanation |publisher=Cambridge University Press |year=1967 |isbn=978-0-521-09445-0 |location=Cambridge |orig-date=1943}}
* {{cite journal | vauthors = Elliot AJ, Reis HT | title = Attachment and exploration in adulthood | url = https://archive.org/details/sim_journal-of-personality-and-social-psychology_2003-08_85_2/page/317 | journal = Journal of Personality and Social Psychology | volume = 85 | issue = 2 | pages = 317–31 | date = August 2003 | pmid = 12916573 | doi = 10.1037/0022-3514.85.2.317 }}
* {{cite book |last=Holmes |first=J |title=John Bowlby & Attachment Theory |publisher=Routledge |year=1993 |isbn=0-415-07729-X |series=Makers of modern psychotherapy |location=London }}
* {{cite book |last=Karen |first=R |title=Becoming Attached: First Relationships and How They Shape Our Capacity to Love |publisher=Oxford University Press |year=1998 |isbn=0-19-511501-5 |location=Oxford and New York |url-access=registration |url=https://archive.org/details/becomingattached00kare }}
* {{cite book |last=Mercer |first=J |title=Understanding Attachment: Parenting, child care, and emotional development |url=https://archive.org/details/understandingatt0000merc |publisher=Praeger Publishers |year=2006 |isbn=978-0-275-98217-1 |location=Westport, CT |lccn=2005019272 |oclc=61115448 }}
* {{cite book |last1=Prior |first1=V |last2=Glaser |first2=D |title=Understanding Attachment and Attachment Disorders: Theory, Evidence and Practice |publisher=Jessica Kingsley Publishers |year=2006 |isbn=978-1-84310-245-8 |series=Child and Adolescent Mental Health, RCPRTU |location=London and Philadelphia }}
* {{cite book |last=Tinbergen |first=N |title=The Study of Instinct |publisher=Oxford University Press |year=1951 |isbn=978-0-19-857722-5 |location=Oxford}}
{{refend}}

== Further reading ==
{{Library resources box|by=no|onlinebooks=no|about=yes|wikititle=attachment theory}}
{{refbegin}}
* {{cite book |last=Schore |first=Allan N. |title=Affect Regulation and the Origin of the Self: The Neurobiology of Emotional Development |url=https://archive.org/details/affectregulation0000scho |date=1994 |publisher=L. Erlbaum Associates |isbn=978-1-135-69392-3 |location=Hillsdale, N.J.}}
* {{cite web | url = https://www.theatlantic.com/magazine/archive/1990/02/becoming-attached/308966/ | first = Robert | last = Karen | title = Becoming Attached | work = [[The Atlantic Monthly]] | date = February 1990 }}
{{refend}}

{{Attachment theory}}
{{Human psychological development}}
{{Parenting}}
{{Evolutionary psychology}}
{{Infants and their care}}
{{Authority control}}

{{DEFAULTSORT:Attachment Theory}}
[[Category:Attachment theory| ]]
[[Category:Adoption, fostering, orphan care and displacement]]
[[Category:Ethology]]
[[Category:Evolutionary biology]]
[[Category:Evolutionary psychology]]
[[Category:Human development]]
[[Category:Interpersonal relationships]]
[[Category:Object relations theory]]
[[Category:Psychoanalytic theory]]