The global phenomenon of unaccompanied immigrant children has increased substantially in recent years in the wake of widespread political instability, violence, and war. Yet, research has not kept pace with these rapid changes, nor does much guidance exist for practitioners in meeting the needs of this highly vulnerable population. The purpose of this special issue of Children & Youth Services Review is to provide a foundation of existing evidence and policy analysis related to unaccompanied children (UC) in different contexts and from a variety of disciplinary perspectives. Below is a brief review of existing literature on this population, followed by an introduction to the Special Issue and its contributions to this emerging body of literature.

The long term poor health outcomes in people who have experienced multiple adverse events in childhood have been well documented since the original CDC-Kaiser study in the late 1990's. Those people who have experienced four or more adverse childhood experiences (ACE) are at significantly increased risk of chronic disease such as cancer, heart disease and diabetes as well as mental illness and health risk behaviours. The ACE pyramid is a model that describes the relationship between ACEs, disease and potentially early death. There is growing evidence of the ways in which adversity and toxic stress, cause these poor outcomes. Exposure to adversity has been shown to alter the molecular and genetic makeup of a child as well as changing the way the neurological, immune and endocrine systems develop and function. Adverse events in childhood are of great public health concern given the evidence of their long term impact on health. This article describes the significant impact of ACEs on the health of future generations outlining the research background to ACEs. It also explores how we are finding ways to mitigate their adverse effects by prevention and promotion of resilience against the effects of adversity.

"Safeguarding children work is complex and challenging. Peer review provides a forum for paediatricians to discuss child protection cases to ensure the management of the child meets accepted standards of practice. The process involves retrospective review of cases, photo documentation, the medical report and multiagency working. It provides a culture of learning, professional development and support, with an opportunity to discuss cases in a suitable environment and to debrief following difficult cases. Clinical governance frameworks identify the importance of peer review and clinical supervision: there are increasing expectations that Health Trusts/Boards will have to provide data on attendance for external review. Both clinical supervision and peer review are forms of reflective practice and developmental activities that give practitioners the opportunity to learn from their experience and develop their expertise within clinical practice. Child protection peer review meetings with clear terms of reference should be set up in all health organisations employing paediatricians working in child protection. All paediatricians should be able to access and attend child protection peer review, supervision and support which should be identified in their job plans. Peer review is recognised as Continual Professional Development. Following discussion any change in opinion is the lead consultant's responsibility. It must be clear that peer review supports the responsible paediatrician in reaching a conclusion and does not provide a formal second opinion to be used in court. Peer review has a role to play in maintaining public and court confidence. It is the paediatrician's attendance at peer review that provides assurance to court that standards are being met, not that the specific case has been peer reviewed. Clinicians who don't attend are at risk of being perceived as maverick.

Child sexual abuse is a clear violation of children's rights with known lifelong devastating consequences. It occurs across all ages, sexes and cultures. Cases are underreported and may not be disclosed at first due to its secretive and hidden nature. It is clear that children do try to disclose but are not always heard or believed. In this paper we delve deeper into the recognition and response to suspected cases of child sexual abuse and the importance of working within a multidisciplinary team to best safeguard the victims. We emphasise the importance of asking questions in a direct, empathic and developmentally appropriate manner, such that the child feels believed and supported. The physical and behavioural changes are described in suspected cases and possible differential diagnoses. We propose a holistic model to the management and prevention of child sexual abuse based on the ecological approach to child maltreatment.

Social determinants of health have long been recognised but their importance is often overlooked. Globally social determinants are responsible for most childhood illness and death. In the UK, conditions which constitute a large part of paediatric practice are socially patterned. Social determinants exert their influence on child health through a complex inter-relationship of more distal social factors such as income and education with more proximal factors such as health behaviours. The pathways by which the social determinants exert their influence operate over time and across generations. Socially related risk and protective factors cluster in different social groups and accumulate over time. Social determinants are profoundly influenced by social and political decisions which are beyond the control of parents and individual paediatricians. Societies can protect children against the adverse effects of social disadvantage. National paediatric societies have a key role in promoting policies which protect children. This brief review summarises the impact of social determinants on children's health in the UK and considers the role of paediatricians in reducing the health inequities generated by these determinants.