Severe antisocial behaviour in children and adolescents has been extremely difficult to change, and the out-of-home methods often used are expensive, may not work, and usually leave the families without a voice in the process. Providing an alternative approach, this book presents a Multisystematic Treatment MST That Focuses On Promoting Behaviour changes within the child's family, peer and school networks. This home and community-based approach is an intensive, short-term treatment that is cost-effective, family inclusive, and has demonstrated both short and long-term effectiveness with families of different cultures and socioeconomic statuses. Following a complete overview of the empirical, conceptual, philosophical and clinical foundations of MST, chapters provide guidelines for implementing MST, including: assessing of family functions, working within the school setting, funding community supports, and conducting individually-orientated intervention. The book concludes with outcomes from controlled evaluations and implications for future policies.