Study context

Questions regarding the most effective way to intervene with families whose children have been placed in foster care led to a major research project in the UK: the BeST^? services trial compared a newly implemented infant mental health approach with social work ‘services as usual’ (SAU). The overall aim was to ascertain which method was ‘best’ for children (i.e., which was most effective and cost-effective) in relation to two main outcomes: their mental health and the time it took them to reach a permanent placement (including a permanent return to their birth family). The Randomised Controlled Trial (RCT) saw 488 infants (age 0–5) randomly allocated to either the infant mental health team or SAU shortly after their entry into care, and their wellbeing was followed up over 2.5 years (after 15 months and then again after 2.5 years). The measures that the research team used, the numbers of children retained in the study, and the overall trial methodology, can be accessed in Crawford and colleagues (Crawford et al., 2025).

The trial was born out of concerns about the mental health and placement instability of children in care. At that time, it was hypothesised that features of an already established infant mental health approach – the New Orleans Intervention model (NIM) – may help to fill some of the gaps that were identified for children and families in the UK context (Minnis et al., 2010). Although NIM had not undergone rigorous scientific testing, preliminary findings suggested success in supporting child mental health (Robinson et al., 2012). ‘Before and after’ comparisons in the USA also suggested that – for children returned to birth families – there was a significant reduction in the repeated maltreatment of children in the study and their subsequent siblings (Zeanah et al., 2001). At the time, this spoke to findings from an audit in Glasgow, where two-thirds of children experienced repeated maltreatment, resulting in a ‘revolving door effect’ of children going back and forth between their birth family and foster care (Minnis et al., 2010).

Throughout the trial, both NIM and SAU undertook a three-month assessment of each participating family based on assessment ‘lenses’ that differ between the approaches: whilst SAU undertake naturalistic observations of the child-parent relationship as part of parenting capacity assessment, NIM follow an approach that is attachment-based using standardised tools. Following the assessment, SAU make a recommendation about whether a child should return home or not, whereas NIM also offer a six- to nine-month trial-of-treatment phase for the family before their recommendation is made. Treatment comprises of evidence-based relationship-focused interventions carried out by their multi-disciplinary team of psychologists, psychiatrists, social workers and psychotherapists. Where parents are unable to engage in the treatment phase, or where it is not safe for them to do so (e.g., if they are still in uncontrolled addiction), NIM will work with the child and their foster carer with the same aim of improving infant mental health.

Differing significantly from the long-standing social work approach to assessing and supporting families with infants in care, the implementation of NIM in a UK context represented a radically different way of intervening in cases of child maltreatment. We followed and researched its embedment journey with interest; from examining its reception in the UK child welfare context (Turner-Halliday et al., 2017) to exploring the views of parents, carers, social workers, lawyers, judges and NIM professionals via interviews and focus groups in what is known as ‘process evaluation’ (Kainth et al., 2022, 2024). The NIM teams recently provided retrospective insight into the challenges they experienced in translating the model between child welfare contexts (in New Orleans, Scotland and England) that all differ significantly from one another, not least in terms of their legal systems (Donaldson et al., 2025).

Purpose of paper

We have already published the main trial findings, which can be condensed into three key messages from Crawford and colleagues (Crawford et al., 2025):

1. There was no difference found between the trial arms in relation to the outcomes measured; that is, children did not significantly differ on mental health outcomes or on the time it took them to reach a permanent placement (i.e., a legal decision about their future) whether they were randomised to NIM or SAU.
2. Whereas it was hypothesised that the NIM approach would produce the best outcomes for children due to its alignment with identified gaps in the UK, the trial’s embedded process evaluation (involving over 200 interviews and focus groups) found that the legal and foster care systems in which the NIM model was embedded did not allow it to be delivered as intended (Kainth et al., 2024).
3. Systemic differences between Glasgow and London led to significant differences between the sites in the time it took children to reach a permanent placement, with major implications also for costs. See Deidda and colleagues (2025) for our full economic evaluation.

Until now, we have not examined what these overall findings, and other findings within the trial, mean for the context of adoption. This paper aims to address this gap, presenting and discussing trial findings that we interpret to be of particular significance to adoption.

Main discussion

Which findings are of most relevance to adoption and why?

Examination of study findings and the extrapolation of those most relevant to adoption was carried out by the research team (all authors on this paper) through focussed discussions.

We identified two main areas of particular significance when an ‘adoption lens’ is taken to the data. These are:

1. What our findings on children’s mental health and rates of neurodivergence mean for adoption.
2. What our findings on children’s journeys to permanent placements mean for adoption.

For each of the two areas, we make various evidence-based recommendations for how adoptive families may be better supported.

Children’s mental health and rates of neurodivergence

Although we found no difference between NIM and SAU in relation to children’s mental health, we can provide insight into children’s mental health and rates of neurodivergence as they came into the study and over the 2.5 year follow-up period:

Mental health shortly after entry to care

Overall, the children in the trial had much higher rates of neurodivergence and psychiatric disorder than the general population: for those children aged 2+ (the age range suitable for the measure of overall wellbeing and development), 40% had at least one diagnosis just after entry to care compared with estimates of 7% to 9% in the general population (Wichstrøm et al., 2012; Gleason et al., 2011). Furthermore, children often spanned multiple diagnostic categories (for a full breakdown: Crawford et al., 2025).

These findings are consistent with previous research that shows the increased prevalence of mental health disorders amongst maltreated children (Engler et al., 2022) and their much higher rates of genetically-linked neurodivergence (Dinkler et al., 2017). They also support what we already know about the likelihood of children presenting with a complex overlap of mental health, cognitive and neurodevelopmental differences (Wilkinson et al., 2025; Minnis, 2013).

Almost a quarter of the children met criteria for an Attachment Disorder upon entry to the study (Crawford et al., 2025). Symptoms include problems with signalling their needs, for example, when they are hurt, hungry or distressed. When problems with seeking or accepting comfort are severe, this is described as Reactive Attachment Disorder (RAD) (Minnis et al., 2013; Lehmann et al., 2020; Zeanah and Gleason, 2015). Some maltreated children have indiscriminate behaviours consistent with Disinhibited Social Engagement Disorder (DSED); in other words, they are likely to wander off without checking back with parents or carers and might even seek comfort from strangers (Lehmann et al., 2020). Most children and adolescents with a RAD or DSED diagnosis have been found to have several co-occurring psychiatric disorders and psychosocial problems (Minnis et al., 2013; Seim et al., 2022).

What do these findings mean for supporting adoptive parents? Recommendations for practice

The fact that, upon entry into care, our cohort of children had a prevalence of psychiatric disorder or neurodivergence that is approximately five times greater than that in the general population is hugely significant in the context of adoption when we consider what we already know about trajectories over time:

Firstly, we know that neurodivergence is an inherent and lifelong aspect of an individual’s makeup, even though its presentation can change and evolve over time. Secondly, whilst some effects of maltreatment may be met by the provision of safe, consistent and nurturing care, other effects can remain over time; for example, mental health consequences (Macpherson et al., 2021) and the indiscriminate behaviours associated with DSED (Kennedy et al., 2017; Sonuga-Barke et al., 2017). Reasons for the persistence of difficulties are clearly multifactorial and include systemic influences (later discussed) that can impact on caregiving environments post-maltreatment. We know, for example, that parenting of maltreated children that is not informed by therapeutic input can perpetuate attachment difficulties, especially if the caregiver only ever sensitively responds to the child’s cues but the child has difficulties in cueing (signalling or communicating) their needs in the first place (Dozier, 2003). It is likely that, in many cases, ‘love is not enough’ and that caregivers need to transcend ‘normal’ parenting to train in more specific skills, including therapeutic skills that aim to reshape the child's internal working model of attachment after maltreatment (Dozier, 2003). Our qualitative work with the NIM team in BeST^? revealed that they had to spend much more resource and focus on facilitating therapeutic skills in foster caring than they had originally envisaged (Turner et al., 2023). This means that children may enter adoption without prior experience of caregiving that has been fully able to meet their needs.

Our findings amplify the call for child mental health services to undertake routine holistic and evidence-based assessments that consider the effects of maltreatment and the potential for neurodivergence (Gajwani and Minnis, 2023; Hiller et al., 2023; Wilkinson et al., 2025), with information from multiple sources (e.g. the child's social worker, teacher etc). When services do not hold the possibility of both in mind, there is the potential to attribute all of the child's difficulties to one origin or the other; thereby limiting the understanding of the child's full range of needs. In the case of Attachment Disorder, it's common co-occurrence with other disorders means that some symptoms can be misattributed to other conditions, like ADHD, and it can be frequently overlooked by services (Davidson et al, 2023). Conversely, when it is known that maltreatment has taken place, there is a risk of explaining all difficulties as related to attachment difficulties or disorders, overlooking the possibility that there may be other impacts on the child's functioning (for example, those related to neurodivergence or PTSD (Hiller et al, 2023). Considering the interaction of both maltreatment effects and neurodivergence is also important; for example, it has been theorised that the interaction can act as an ‘additive' risk and pose threats to mental health that are doubly impactful (Gajwani and Minnis, 2023). Early identification is therefore key and although many adoption training and education resources can provide vital information, support and advice, they cannot replace the need for mental health services to formulate the needs of an individual child, whose overlapping difficulties may require specialist assessment (Davidson et al., 2023) and an understanding of the complex, multi-level processes involved in promoting resilient functioning after maltreatment (Ioannidis et al., 2020).

Holistic, evidence-based, assessment is vital in helping adoptive parents to recognise and understand their child’s needs as they enter adoption, in order to make early and informed decisions about the many different factors involved in their child's care; for example, choosing where and when to seek support, choosing how to adapt their parenting and home environment, and choosing the types of modifications to the child’s educational environment that they might want to advocate for. The distress that adopters experience when they have not been able to have informed expectations, or make informed preparations, have already been reported (Bejenaru et al., 2024). Considering that carers and adoptive parents also report a general lack of information about their child’s background and experiences (Whincup et al., 2019), and that foster carers can under-report or normalise children's complex difficulties (Pritchett et al, 2016; Turner et al., 2023) there is a risk that - without standardised early assessment - adoptive families can be left ‘in the dark' when it comes to a nuanced understanding of their children's needs. Furthermore, if adopters are not aware of common symptoms or characteristics (and routine assessment is not built in as standard), they may not seek help from services, or may not know what form of help is most appropriate to seek. Consequently, there is an ongoing risk of unmet need, which has the potential to impact negatively on whole family functioning over time.

Beyond assessment, many adoptive families need timely support and intervention. Their knowledge about their child’s difficulties does not automatically translate into effective parenting strategies or constructive adaptation of the child's environment without specialist input, which may include the aforementioned need to develop a therapeutic approach to parenting (Dozier et al, 2013). The symptoms associated with Attachment Disorders can be particularly challenging for the development of intimate relationships in new caregiving environments – and thus in adoption – because they disturb multiple domains of social functioning and therefore how the child relates to others (Guyon-Harris et al., 2019). Symptoms of RAD, for example, may only get better - in some cases - if the adoptive parent gains therapeutic skills like ‘gentle challenge,' which can improve the child's ability to seek and accept comfort and help. These types of therapeutic skills are unlikely to be intuitive, and it is recognised that they can actually go against our natural instincts as caregivers, meaning that they have to be learned and practiced through specialist intervention (Dozier, 2003). The challenges of parenting neurodivergent children after adoption are also known (Hunt and Rodwell, 2018) and this can be especially complex if the child also has maltreatment-related behaviours that can result in them being less able to seek or accept parental support. Whilst children who are neurodivergent (including ADHD, Autism, Tic Disorder and Developmental Coordination Disorder) can thrive with the right adaptations to their environment, families might need specialist support, especially if children are resistant to parental support (Hunt and Rodwell, 2018).

Whilst the need for early intervention is clear, it has been shown that there is a lack of evidence-based and consistent treatments to improve attachment in young children (Wright et al., 2023), and a lack of fully tested treatments for the complex overlap of maltreatment-related difficulties. One way to support adoptive families, therefore, is to advance knowledge and practice through intervention research. With anecdotal evidence suggesting positive effects of Dyadic Developmental Psychotherapy (DDP) (e.g. Burch et al., 2023), we are currently carrying out a large-scale RCT of DDP with adoptive families in order to examine its effectiveness (Turner-Halliday et al., 2014; Biggs et al., 2025). The results will be known in early 2027.

Advancing our understanding of ‘what works' for adoptive families needs to be a key goal in this context because we continue to discover an overall lack of support in our various strands of research. Adoptive parents in our RCT of DDP voice concern over a lack of access to assessment and intervention when seeking help (Biggs et al., 2025) and highlight the significant difficulties they encounter in navigating an extremely complex service landscape (Aleid et al., 2026). Often, these barriers can be even greater than those experienced by foster carers because of the lack of specialist child and adolescent mental health services available for adoptive families. They can also be greater because of the way that services view and respond to maltreated children’s difficulties (Hiller et al., 2023), for example, if they attribute all difficulties to maltreatment and overlook neurodivergence. Concurrently, there are barriers to accessing general infant mental health services (Hickey et al., 2024; McFadyen, 2024) and, as mentioned above, the BeST^? services trial demonstrated that the NIM intervention could not be delivered as intended in the UK due to barriers created by the legal and foster care systems (Crawford et al., 2025). Taken together, multiple barriers mean that adoptive families can often be left ‘holding the baby’ when trying to meet the complex needs of their child.

Mental health over time

When we followed up the cohort of children over the 2.5 years, neurodivergence tended to be stable over time, whereas Attachment Disorders decreased in the cohort over the period. We also gleaned interesting insights into the potential complexity of children’s mental health profiles over time when we examined the effects of foster carer commitment on the children’s symptoms of attachment disorders and mental health problems. Foster carer commitment is defined as ‘a motivation to have an enduring relationship with the child’, also implying emotional investment in the child (Dozier and Lindhiem, 2006). Whilst we found that symptoms of RAD significantly improved by the 15-month follow-up point when infants experienced a highly committed initial carer, high levels of foster care commitment were significantly associated with higher levels of mental health problems at the 2.5 year follow-up point (Turner et al., 2022).

Our findings in relation to RAD were what we expected, but the findings in relation to the effect of high commitment on mental health were more puzzling. Firstly, mental health getting worse rather than better suggests that maltreated children’s difficulties may not simply improve over time. Secondly, the fact that we did not find this effect until 2.5 years after the children entered care suggests that there may be delayed effects of committed caregiving on a child’s mental health. Interviews with caregivers and clinicians suggest that our findings may reflect a process where children are ‘letting it out’ as they become comfortable and less inhibited with highly committed caregivers. A ‘honeymoon period,’ where children’s difficulties are less visible, may be likely. Alternatively, or in addition (and since our measure of mental health functioning was based on foster carer report), foster carers may become better at noticing symptoms in the child as time goes on. This is consistent with other studies, for example Staines and colleagues (2019) who suggest that adoptive parents’ perception of child behaviour changed throughout the process of DDP as their empathy increased, resulting in an unexpected increase in reports of emotional distress in the children following DDP. We are keen to carry out longitudinal research that follows the children up over a number of years, where we hope that the improvements in mental health that been found in other longitudinal studies of adopted children are also seen in our cohort; for example, from the Bucharest Early Intervention Project (Smyke et al., 2012; Smyke et al., 2002, Zeanah et al., 2017) and The English and Romanian Adoptees Study (O'Connor et al., 1999; Sonuga-Barke et al., 2017).

What do these findings mean for supporting adoptive families? Recommendations for practice

Committed foster care has been shown, in previous research, to be associated with a greater likelihood of a long-term placement or adoption (Dozier and Lindhiem, 2006), fewer reported behavioural problems in children (Lindhiem and Dozier, 2007), and carer's expressions of delight in the relationship (Bernard and Dozier, 2011). It is also theorised to be foundational to the development of a healthy attachment relationship between child and carer (Bernard and Dozier, 2011). Our findings in relation to its positive effect on RAD (and on mental health if these changes are positive in the end) evidence its importance, yet we found that there were more barriers than drivers to infants in foster care experiencing committed caregiving in our current system of care (Turner et al., 2023). Unsurprisingly, therefore, measured commitment has been shown to be higher amongst adopters and more variable amongst foster carers (Cleary et al., 2018), meaning that many children may be more likely to experience a highly committed relationship in adoption. Although BeST^? did not track children long enough to examine whether adoption led to better outcomes than temporary foster care (the numbers of children adopted by 2.5 years were too minimal for analysis), the positive effects of high commitment in Turner et al (2022) suggest that 'a motivation to have an enduring relationship with a child' matters.

The fact that we did not find a relationship between high foster carer commitment and increased mental health problems until 2.5 years down the line (Turner et al., 2022) is significant for adopters and supports the call for ongoing holistic assessment (as described above) that extends beyond entry into care (Gajwani and Minnis, 2023; Hiller et al., 2023; Wilkinson et al., 2025). After time in foster care, adopters might expect that the children who join their family will continue with a linear progression of positive recovery. So, when children settle into the family and only then begin to display difficult behaviours, or if symptoms of difficulties are better identified over time, adopters might blame themselves and services may attribute the pattern to problems with parenting capacity. Although we suspect that ‘letting it out’ may be a healthy sign of progress for the child that implies committed care, or that the increasing ability of parents and carers to notice difficulties is equally progressive and may increase help-seeking from services, these changes may not be received as such by adoptive parents. If adopters attribute the child’s difficulties to perceived deficits in their parenting, for example, this may, instead, decrease their likelihood of seeking help from services. This is a crucial point at which the adoption itself might begin to be under strain and there is even the potential for adoption breakdown at this vulnerable time.

It is vitally important that adopters are aware of these patterns as this is the point in the family journey when they most need help from services to support the child and to believe in their ability as parents. In addition to the evident need for ongoing assessment and support as described above, we suggest that adopters’ understanding of the differential effects of committed care on Attachment Disorders compared to mental health is important. This can be supported by assessment in both research and practice that looks at Attachment Disorder symptoms separately from those of mental health problems so that a more nuanced understanding of the recovery journey, across time, can be gained.

Children’s journeys to permanent placements

Young children living in liminal spaces

It has been known for many years that later entry to care and later adoptive placement is associated with a higher likelihood of child mental health problems, therefore timely decision-making is crucial if a child has been maltreated. Yet, only a quarter of the children in the BeST^? cohort were in a permanent placement by 2.5 years indicating that – by the time children reach adoption – the majority have been living in the ‘temporary’ care system for significant stretches of infancy and early childhood. Because our follow-up ended after 2.5 years, we are unable to say when, on average, children eventually moved on from temporary foster care and a further follow-up of the cohort would be helpful in this regard. A previous large-scale tracking of young children’s pathways through care in Scotland found that most adoptions did not take place until three to four years after the child had entered care (Biehal et al., 2019).

Our qualitative work with foster carers throughout the trial suggests that these prolonged timescales are ‘the norm.’ It was clear that foster carers, who described significant emotional investment in their children, were hugely concerned about the breaking of attachments after such lengthy periods. Although foster carers saw their role as a necessary ‘bridge,’ they also perceived that the timescales for infants had gone far beyond a bridging function, creeping into the territory of causing harm and delaying adoption:

He didn't get adopted until fifteen months – that seemingly is a success story because he was ‘only’ fifteen months…he eventually got adopted by a couple who already had his two siblings. They [social workers] knew before he was born that he would never go home and his parents would never get him…why was he with me for fifteen months? And why is that an achievement? … He was so attached to us, and we were so attached to him at fifteen months, and it would have been so much better if he had been moved on so much quicker and had his ‘forever’ family so much quicker (Turner et al., 2023).

As we describe in Turner and colleagues (2023), the detrimental impact of living in a state of uncertainty – or liminality – has been researched in other contexts and it was a key theme throughout the process evaluation of the trial. Our qualitative work represents the emotive perspectives of apparently ‘short-term’ foster carers in being unable to provide any type of certainty to the child over prolonged periods of time. This was mostly about uncertainty in relation to when the child would move from foster care to adoption:

She has been with me for nearly three years, and she has known a long time ago that she is not going back, and she knows that….it is the whole not knowing for the child I think is the worst bit. ‘Am I going to be here at Christmas?’ ‘Am I going to be here at my birthday?’ ‘Am I going to be here then when we go on holiday?’ I think that's the worst part for the child… . I will say ‘I don't know either’ and it is quite difficult …. you know, we are trying to arrange a family holiday as well; I don't even know if she is going to be here (Turner et al., 2023).

Infants living in states of uncertainty, with temporary caregivers (who can have variable levels of commitment (Bernard and Dozier, 2011) is the opposite of what we know that infants need for healthy development. Infancy is a crucially sensitive period for socioemotional development (Zeanah et al., 2011; Zeanah and Humphreys, 2018) and, whilst abuse and neglect during these periods can be particularly harmful, the converse also applies in that early childhood holds the greatest opportunity for sustainable change and recovery post-maltreatment (Chinitz et al., 2017; Tarren-Sweeney, 2014). Whilst we have seen the positive impact of committed foster caring on our infants (Turner et al., 2022), the prolonged uncertainty that our findings evidence has the potential to not only cause harm but to waste a vital opening for maximising opportunities for recovery.

Age

Age of entry into care is also significant for the adoption context. We found that, for every month older at entry to care, the probability of being placed in a permanent placement (home or adoption) decreased by 2.4% and the probability of reaching a permanent placement plateaus at 66% at around eight years (Kainth et al., 2024). Carer commitment is highest when the child is placed at a younger age (Dozier and Lindhiem, 2006) and this further underscores that – for infants in care – time is of the essence if they are ever to experience stable, committed care.

Location

Although we found no differences in timescales between NIM and SAU, we found that children in London reached a permanent placement more than four times quicker than those in Glasgow. Our qualitative process evaluation suggested that the Scottish legal system (with a lack of judicial oversight and legally imposed timescale) contributes significantly to delayed decision-making. Consequently, our economic evaluation found that costs of infants in care in Scotland were almost twice those in England (Crawford et al., 2025; Deidda et al., 2025).

Our qualitative work also noted that the lack of judicial oversight led to the child’s voice not being heard in the forums where decisions about them were being made. From a rights perspective, this is contrary to UNCRC article 12 (the right of effective participation). Adopters in different geographical locations (with different legal systems) may therefore experience different impacts of drift and delay on their child.

What do these findings mean for supporting adoptive families? Recommendations for practice

Our findings regarding timescales are highly significant for adopters because they highlight the potential for systemic harm before a child enters their care. Just over 70% of the infants and young children in our cohort were still living in temporary foster care 2.5 years after entering care. Children who enter adoption after truly ‘temporary’ foster care are therefore in the minority, meaning that many adopters are caring for children who have lived in contexts of prolonged uncertainty after maltreatment, in a system where the child’s foster carers are likely to have experienced multiple barriers to committed caregiving (Turner et al., 2023).

Some authors doubt the attainability of reform in the child welfare system (Kotlar and Tiemeier, 2025), but the significant differences in timescales to permanency we found between neighbouring jurisdictions demonstrates that outcomes for children can be largely dependent on (changeable) systemic factors. We have made recommendations for strong judicial oversight of cases of maltreatment in Scotland (Crawford et al., 2025; Kainth et al., 2024).

We have also recommended a move to a dual registration system for infants in care in the UK – this is a system where adopters are registered as foster carers so that, if the child cannot return home, there is no need for a further breaking of the attachment relationship with the foster carer (Crawford et al., 2025; Kainth et al., 2024). This is routine practice in some other countries already (including in New Orleans where the NIM model originates) and there are small numbers of dually registered carers in the UK. The empirical supportive evidence we provide here should provide a strong driver for change.

Distilling the implications for adopters and adoption processes, we recommend dual registration and timely permanence processes on the following bases:

Children who cannot go home, and need to be adopted, would reach their adoptive family much quicker than they do at present: A dual registration system may mitigate against delay and potential harm. Our findings related to legal system impacts on timescales, barriers to commitment in foster care and the decreasing likelihood of children finding a permanent placement as their age increases, would be mitigated if children were in placements designed to be permanent if they could not go home.

Furthermore, our findings on commitment in Turner and colleagues (2022) suggest that systems should maximise the chance of infants experiencing committed care as soon as possible. Although commitment implies emotional investment in the child, foster carers having ‘motivation to have an enduring relationship with the child’ is likely to be compromised in a system based on temporariness.

A dual registration system for infants would mean only one placement move, if it was decided that the child could not be safely reunified with their birth parents: Although we know it is better for infants to have experienced healthy attachment relationships - even if temporary (Garcia Quiroga and Hamilton-Giachritsis, 2016) - this does not mean that the breaking of attachments is not harmful. The foster carers who took part in our qualitative process evaluation powerfully described the stress of the ‘breaking of attachment’ phase, not just for themselves, but for infants. In the context of developmental age and understanding of the situation that they are immersed in, foster carers felt it particularly harmful that children would ‘just not know’ where they had gone. Yet, they also normalised it as ‘just part of fostering’:

I think it is quite sad that I've had this wee boy since he was seven months and he is now two years…I think it is such a shame that a child can be with you all that time and then he is obviously going to get adopted and it just worries me; how he is going to cope with that? Because he is so attached to me and my partner and all my family and you think when he goes up for adoption where would he think we were? And it upsets me… but that's just part of fostering, isn't it? I just feel the children shouldn't be left as long as that (Turner et al., 2023).

With significance for the child’s development of relationships in adoption, further research is needed on the impact that prolonged uncertainty experienced by both children and foster carers might have on the formation of healthy attachment relationships in foster care.

A dual registration system may also increase the likelihood of the most adequate support for the mental health problems that we found on entry to care: Mental health intervention for infants and young children is largely relational, i.e. we know that infant mental health is dependent upon the quality of their relationships, and we therefore know that relational methods are most likely to bring about positive change (Bakermans-Kranenburg, 2003). However, the NIM team have already expressed the challenges that they experienced in working with temporary infant-carer relationships:

We are talking about long-term attachment patterns and they [foster carers] are working to a short-term time span (Turner et al., 2023).

In the US, where NIM originates, there is a dual registration system surrounding the NIM approach, which may partially explain why we did not find hypothesised benefits in the UK context.

As already described, the need for early mental health intervention for infants is also well known. If infants were placed with prospective adopters from the outset, relational work could be carried out with the child and with their permanent caregivers as early as possible. Furthermore, with the reductions in RAD that we found in relation to committed care (i.e. a motivation to have an enduring relationship with a child), children may have a better chance of a quicker recovery from RAD in a dual registration system.

Adopters would experience – first hand – the child’s recovery process straight from situations of maltreatment: We have demonstrated the possibility of complex, non-linear, recoveries of children after abuse and neglect where challenges may not surface initially (Turner et al., 2022). It could be that a dual registration system allows adopters to be part of the child’s recovery journey prior to the later ‘letting it out’ phase, but during improvements in RAD, allowing adopters to understand and experience the child’s changing needs in a first hand way. It may also be that, by receiving the child straight from the birth family, adopters receive information about the child that has not been diluted through multiple placement moves.

The timescales involved in bringing about improvements in (birth) parenting, may be less of a challenge in a dual registration system: Throughout the trial, the question over ‘how long should birth parents be given to change?’ was a prevalent discourse with conflicting perspectives about what constitutes a timescale that is in the best interests of the child (Turner-Halliday et al., 2017; Turner et al., 2023). There are some birth families for whom return of the child would have been possible, with sufficient time for therapy while their child was in a stable dually-registered placement. In a dual registration system, there may be less pressure on parents to enact change within tight timescales, and less pressure on services to evidence change to courts (in England) and Children’s Panels (in Scotland) because their placement with a dually registered carer would not be affected if there were challenges in the birth parent’s progress. A dual registration system may therefore support parents to be able to complete rehabilitative intervention.

Conclusions

By testing an infant mental health intervention in the UK child welfare context, the BeST^? services trial has learned much about infants in care. Not only have we shone a spotlight on systems surrounding cases of maltreatment, we have also learned much about the children themselves; their mental health, neurodivergence and journeys through the care system. This allows us to make recommendations for practice that are grounded in robust research data from a sizeable cohort of 488 children and from over 200 sources of qualitative data in the systems that surround them. In this paper, we have had the opportunity to examine, in-depth, what our findings mean for the context of adoption.

Firstly, our findings in relation to mental health and neurodivergence underscore the need for evidence-based and holistic assessment from the start, along with access to specialist intervention where required, so that adopters are fully equipped with the knowledge that allows them to make informed decisions about how to best meet their child’s needs. This requires a systemic response to improving outcomes for maltreated children, where adoptive parents are not left ‘holding the baby’ when it comes to addressing needs that are often significant, prevailing, and where the parenting skills required can go beyond – and against – our natural instincts and expectations as caregivers.

It is not only the range and persistence of children's difficulties that can be complex; our findings also highlight the complexity of the recovery journey and the need for ongoing assessment and support as children’s needs (and therefore adopters’ needs) change over time. Although the ‘peaks and troughs’ or ‘rollercoaster’ view of recovery may already resonate well with caregivers and clinicians alike, our findings on the effects of committed foster care on infants provide an evidence-base upon which we can demonstrate this pattern. The complex non-linear recovery for children who have experienced maltreatment requires much more research as we believe this knowledge is essential for informed adoptive parenting that is supported by evidence-based practice.

Secondly, our findings demonstrate that delays and living in states of liminality are unacceptable for young children and those caring for them, leading to us calling for legal system change (Kainth et al., 2024). They go against everything we know about what young children need for optimal development and pose a threat to their chances of optimal recovery in adoption. Whilst the need for systemic improvements may seem obvious, one of the most significant barriers to change is the normalisation that children in foster care will stay for years in ‘temporary' and uncertain circumstances whilst forming attachments that one day will be broken. When we think of children in biological families and our expectations for their attachment relationships, this ‘normal' seems anything but.

In this article, we have unpacked the rationale for a change in the UK to a system of dual registration for infants, which we believe would be twofold in its impact: firstly, it would mitigate against many of the problems that our data evidence (e.g. delay and uncertainty in temporary foster are) and, secondly, it would maximise the likelihood of key conditions that have been shown to aid recovery (committed caregiving without inherent attachment disruption). It seems imperative to now gather the views of groups who we are yet to consult, such as dually registered carers and those working with care-experienced children and young people in mental health and social services. Such data can help us to better understand the potential drivers of, and barriers to, system change.

The recommendations we make are crucial building blocks if adopted children are to have the best chance of healthy development after maltreatment. Consider a six-year-old boy adopted after two temporary, but prolonged foster placements and now on the verge of adoption breakdown. His ADHD was missed due to a lack of mental health assessment, and his foster carers were unable to tolerate persistent ADHD-related sleep difficulties. This little boy has suffered the loss of multiple caregivers and, when finally placed with his prospective adopters, he lacks the trust needed for this relationship to be a success. For such children, a system that overlooks their needs and that normalises prolonged uncertainty and attachment disruption can be devastating. Conversely, a system that prioritises routine early assessment, specialised intervention, and immediate pathways to permanence has the potential to empower such children to thrive.

Our recommendations for practice are all related to systemic change; by adding and improving access to services, or by changing the features of systems that are likely to cause harm. BeST^? has demonstrated that, with the right research methods, we can identify the specific features of systems that are acting as drivers and barriers in terms of positive outcomes for infants; for example, with the vast timescale differences that we have evidenced between England and Scotland, we have been able to identify that the primary systemic divergence is rooted in the legal system (i.e. the presence, or lack, of judicial oversight of cases.) Like children’s trajectories after maltreatment, such features are inherently changeable. This gives us hope that our growing research evidence in this landscape will provide the empirical base needed for systemic change, to ultimately give infants and their families the best chance at a supported and stable future.

Recommendations at a glance

Our findings support the following recommendations.

Assessment and training amongst services

• An evidence-based holistic assessment of every child entering foster care by mental health services, which considers both neurodivergence and impacts of maltreatment. Assessments should be ongoing over time (with cognisance of the fact that needs are changeable over time).
• Better awareness and training of Attachment Disorder symptoms (RAD and DSED) amongst mental health and social work teams, whilst supporting these teams to understand the common overlap of maltreatment effects with neurodivergence.
• All services should be informed about the impacts of committed caregiving; that is, children may seem to ‘get worse’ in committed care before recovery is possible. This has clear implications for decisions about placements, for example, a child showing an increase in difficulties may not reflect negatively on the input of the caregiver.

Support and training for adoptive parents

• Support and training for adoptive families that is fully informed by mental health assessments. This needs to be firstly, bespoke in relation to the individual child and their unique profile of needs, and secondly, ongoing, in relation to the changeability of needs that we have demonstrated, particularly as infants enter committed caregiving contexts. Social work teams will require the support of clinicians to develop such training, which may include the need for adoptive parents to learn therapeutic skills that are unlikely be intuitively developed.
• Support and training for adoptive parents that highlights the complexity of the post-maltreatment journey, including delayed effects of committed caregiving that could see the child seemingly ‘getting worse’ over time. This is crucial in supporting parenting confidence and help-seeking from services.
• Awareness-raising amongst adoptive families about the symptoms of Attachment Disorders so that help-seeking is encouraged. Understanding the differences between typical sociability and socially disinhibited symptoms related to DSED, for example, may lead to better identification of when children need help.

Timescales for infants in foster care

• Foster care system change: Infants should be placed with adopters who are dually registered as foster carers so that:
  • The likelihood of infants experiencing committed caregiving is maximised as early as possible.
  • If the child cannot be returned to parental care, there is no further placement move, mitigating against the known harm caused by multiple disruptions of attachment at a crucial stage of child development.
  • In situations where birth parents require time to improve parenting capacity, the child does not have to move foster care placements in that time.
  • In cases where it is known that the child cannot return to birth parents, children and foster carers do not live in prolonged states of ongoing uncertainty about when adoption will happen.
  • Children reach their adoptive parents straight from situations of maltreatment, meaning that the recovery journey exists within a stable and committed relational context. This maximises opportunity for early attachment-based intervention with relationships that are permanent.
  • Adopters experience, first hand, the recovery journey as early as possible, maximising firstly, their understanding of the child and the recovery journey; secondly, their ability to have input into the child’s recovery and development as early as possible; and thirdly, their ability to have information about the child that is not lost through multiple placement moves.
• Legal system change: Recommendations for legal system change are already made elsewhere (Crawford et al., 2025; Kainth et al., 2024) with the key message being that any legal system that is responsible for infants in care needs to have strong judicial oversight that does not allow for unnecessary drift and delay. For adoption, this means that:
  • If a dual registration system was implemented, the child and their prospective adopter would not live in a prolonged state of uncertainty about whether the child is to return home or not.
  • The effects of the child’s increasing age that were found (reducing their likelihood of reaching any form of permanence) would be mitigated against.
  • There is hope that judicial oversight would hold the infant’s voice at the centre of decision-making.