Introduction

      Attachment theory originates in the work of the British psychoanalyst and child psychiatrist John Bowlby and the Canadian clinical psychologist Mary Ainsworth. Bowlby sought a scientific explanation for the affectional bonds that children form with their caregivers, as manifested by attempts to seek and maintain proximity to and comfort by their caregivers, and by negative reactions following prolonged separations and losses. He eventually formulated the core tenets of attachment by drawing from multiple scientific disciplines, including ethology, psychoanalysis and cognitive psychology (Van der Horst, 2011). Bowlby’s emphasis on the importance of early care may come across as self‐evident today. However, it was anything but an orthodox position when he formulated attachment theory, at which time the importance of children’s actual experiences with their caregivers were not sufficiently acknowledged (Bowlby, 1940, 1951, 1969/1982). Ainsworth, who collaborated closely with Bowlby, then extended his account by conducting extensive empirical observations of caregiver–child interaction, and by identifying individual differences in infants’ expectations of the availability of their caregivers (Ainsworth et al., 1978; Van Rosmalen et al., 2015, 2016).

      Already in their lifetime, their work influenced various aspects of policy to do with children. One important shift to which they contributed was recognition of the negative effects of hospitalization for children when, as was common policy, their caregivers were not permitted to visit or allowed to visit only very irregularly (Bowlby et al., 1952; Van der Horst & Van der Veer, 2009). Ideas from attachment theory have also been influential for parents, teachers, child protection services and policy‐makers. Key concepts and ideas that entered into circulation included Bowlby’s emphasis on the importance of early care for socioemotional development, his concern about major separations of infants from their caregivers, and his emphasis on the value of continuity in child–caregiver relationships. Ainsworth’s ideas also gained recognition, particularly her identification of the importance of caregiver sensitivity for children’s socioemotional development. She is also known for her account of the sensitive caregiver as a “secure base” from which the child can explore the environment, and as a “safe haven” to which the child can return for comfort and protection. For instance, the “First 1000 Days” policy agenda acknowledges the developmental importance of early care, and makes explicit reference to attachment theory (House of Commons Health and Social Care Committee, 2019). Further, preschool curricula often make reference to attachment theory and the importance of creating a secure base to facilitate children’s exploration and, through this, their learning.

Since the passing of Bowlby and Ainsworth in the 1990s, ideas about attachment seem to have become more, rather than less, appealing and popular. One reason may be their alignment with current concerns about the importance of early experience for brain development (Gerhardt, 2014; Wastell & White, 2017). In a 2018 survey conducted by the British government of organizations working with children in need of help and protection, attachment theory was, by a large margin, cited as the most frequently used underpinning perspective (Department for Education, UK, 2018). In social work policy and practice, Smith and colleagues (2017) have argued that attachment theory “has become the ‘master theory’ to which other ways of conceiving of childcare and of relationships more generally become subordinated” (p. 1606). In family courts, attachment theory and research is referenced in relation to children’s best interests and used to inform decision‐making (Keddell, 2017).

      Yet the account of attachment theory and research that is available in much clinical and child welfare practice, as well as in popular and policy contexts, can sometimes be distorted or hazy (Furnivall et al., 2012, Reijman et al. 2018; Morison et al., 2020). For instance, popular accounts of attachment theory often miss Bowlby’s (1988) qualifications of his earlier emphasis on the importance of early care: in his later work he placed emphasis on the potential for both continuity and change in psychological development. The popular account of attachment theory likewise misses that Ainsworth was using a technical definition of “sensitivity.”. She meant the ability of a caregiver to perceive and to interpret accurately the signals and communications implicit in a child’s behavior, and given this understanding, to respond to them appropriately and promptly. This meaning is not implied by uses of the word “sensitive” in ordinary language, which is typically assumed to mean warm and caring. Popular accounts of attachment theory also tend to overestimate the amount of information that can be gained from observations of individual persons’ attachment quality (e.g. Granqvist et al., 2017). It has recently been highlighted that popular accounts of attachment theory sometimes influence family court decision‐making, resulting in a large number of attachment scholars writing a consensus statement with recommendations for how to use attachment theory and research in decision‐making concerning child protection and child custody (Forslund et al., 2021).

      Already in 1968, Ainsworth wrote to Bowlby with concern: “attachment has become a bandwagon” – a popular and oversimplified cause. She specifically worried that a breakdown of communication was occurring between active attachment researchers and their publics, causing both excessive enthusiasm for the paradigm in some quarters and unfair rejections in others. Furthermore, appeals to attachment by practitioners often neglected what she considered essential about the paradigm, for instance by focusing on laboratory‐based classifications of infants’ attachment quality rather than on their perception of the caregiver’s availability based on their actual experiences of care (see also Ainsworth & Bowlby, 1991).

      What factors contributed to this bandwagon? One was that Bowlby was a great popularizer. He used television, radio, magazines and books published by the popular press to get his key messages out to clinicians, policy‐makers and the wider public. However, Bowlby knowingly simplified his messages in these forums, and he often kept his more subtle conclusions and qualifications for his scholarly work. Indeed, he was explicit that in his popular writings he exaggerated matters; it was a kind of marketing strategy for his more complex theoretical reflections (see, e.g. Bowlby, 1987). While this strategy created a version of attachment theory that could circulate much more easily, it was in some important regards a misleading or even distorted picture of his conclusions.

      The cut‐price popular account of attachment that Bowlby set in motion was evocative, provocative, quite general and had the appearance of scientific credibility. This contributed to its flexibility, its urgency and its exceptionally wide appeal to various people concerned with family relationships and child development (Duschinsky, 2020). For instance, Bowlby’s warnings about the dangers of child–mother separations were too imprecise. Major separations are indeed potentially harmful for young children (for a discussion, see, e.g. Forslund et al.,2021). However, in failing to qualify what kinds of separations he was writing about, Bowlby conveyed the impression that even ordinary separations, including limited use of day‐care, was a risk factor for long‐term harm. By contrast Ainsworth gave no public interviews, and she never wrote a magazine or popular article. Her energies were firmly focused on establishing the scientific basis of attachment as a research paradigm. With exceptions such as Patricia Crittenden (e.g. Spieker & Crittenden, 2018), and Peter Fonagy (e.g. Fonagy & Higgitt, 2004), the next generation of attachment researchers followed Ainsworth’s approach of focusing on research and ignoring public understandings and misunderstandings of attachment. As Susan Goldberg (2000) observed, after Bowlby “many attachment researchers (myself included) have been reluctant to take on this responsibility” (p. 248). This left popular misunderstandings influenced by Bowlby’s crudest statements too frequently unchallenged.

      Half a century later, important theoretical papers and empirical studies conducted by the successors of Bowlby and Ainsworth are often stuck behind paywalls and in books or encyclopaedias that are out of print or otherwise out of reach of potential readers. It is far too difficult for practitioners and publics to access attachment theory and research, and some of the books specifically targeted for practitioner audiences contain serious inaccuracies (e.g. Pearce, 2016). It is no wonder, then, that the image in wider circulation differs from the views held by attachment researchers (Duschinsky