Classic research in juvenile delinquency is near unanimous in suggesting that there are several routes through which young people become at risk for delinquency. The overall findings of studies of delinquents and nondelinquents are very strong and very clear; the ability to distinguish between delinquents and nondelinquents increases dramatically when a number and variety of major risk factors are surveyed. The risk principle assists in deciding who might profit most from intensive rehabilitative programming. The need principle suggests the appropriate targets of change for effective rehabilitation. Responsivity has to do with the selection of the appropriate modes and styles of service. The available evidence suggests that the real action for purposes of reducing criminal recidivism resides in creating correctional settings in which correctional professionals may design, deliver, and evaluate the effectiveness of rehabilitative programs. 3 figures and 12 references