Over the last two decades, researchers have made significant discoveries about the causes and origins of delinquency. Specifically, they have learned a great deal about adolescent development and its relationship to decision-making, about multiple factors that contribute to delinquency, and about the processes and contexts associated with the course of delinquent careers. Over the same period, public officials have made sweeping jurisprudential, jurisdictional, and procedural changes in our juvenile justice systems. The Oxford Handbook of Juvenile Crime and Juvenile Justice presents a compilation of critical reviews of knowledge about causes of delinquency and their significance for justice policy, and about developments in the juvenile justice system to prevent and control youth crime. The first half of the text focuses on juvenile crime and examines trends and patterns in delinquency and victimization, explores causes of delinquency—at the individual, micro-social, and macro-social levels, and from natural and social science perspectives—and their implications for structuring a youth justice system. The second half of the book concentrates on juvenile justice and examines a range of issues—including the historical origins and re-invention of the juvenile court; juvenile offenders' mental health status and considerations of trial competence and culpability; intake, diversion, detention, and juvenile courts; and transfer/waiver strategies—and considers how the juvenile justice system itself influences delinquency.