Written for professionals spanning children's services, this must-read guide provides an authoritative overview of what shapes the psychological wellbeing of children and young people - from perinatal care and adverse childhood experiences (ACEs) through to their socioeconomic circumstances, schools and the wider community. Contributors provide a concise overview of the evidence base, identifying current barriers to good mental health in policy and service provision, and highlighting examples of initiatives proven to be successful. Examples are drawn from health, social care, youth justice and education settings with a focus on preventative and early intervention measures. This book is a rich resource for all professionals concerned with child wellbeing, including service providers, commissioners, professionals and students. It should serve as essential reading for students on mental health training courses.