This volume is the result of an EU project involving two different European countries (Italy and Cyprus) on risk and needs assessment for juvenile violent offenders. The book is based on a longitudinal data base of juveniles who have committed violent crimes and who have been followed up after 6 months to measure their recidivism rate. The aim of the book is to provide practitioners who are dealing with juvenile (violent) offenders, with scientifically-based theories and knowledge derived from results about risk assessment. In particular it shows how a newly developed and tested instrument/approach, the EARN (European Assessment of Risk and Needs) works and how it can be used to help practitioners. Recidivism of violence in juveniles is based on several risk factors and is reduced on the basis of protective factors. Efficient legal intervention and treatment are more and more tailored according to the risk factors but also to the needs of juveniles. Juvenile Justice Systems in Europe tend to approach the juvenile who has committed a crime not only from a sanction point of view but more as an opportunity for the juvenile, his or her family and the social context in general, to reduce the risk of recidivism. This book will be of interest to researchers, students, social workers, police officers and lawyers.