The 2008 UK government Youth Crime Action Plan emphasises prevention and early intervention in different aspects of work with young people who offend or are considered to be 'at risk' of offending. Much of this approach includes targeted work with families and work to reduce the numbers of young people entering the youth justice system. This report takes a critical look at early intervention policies. Through contributions from leading experts on youth work and criminal justice it considers the development of integrated and targeted youth support services and the implications for practice of early intervention policies; analyses the causes of serious violent crime through consideration of issues that address gangs and guns; provides an evaluation of the government's early intervention strategy through the examination of its Sure Start programme and other family initiatives; identifies the psychobiological effects of violence on children and links them to problem behaviour; considers the impacts of family intervention projects and parenting work and compares approaches to early intervention across different jurisdictions and examines the lessons for practice in England and Wales.