A review of forty past or continuing attempts at the prevention of juvenile delinquency leads to the nearly inescapable conclusion that none of these projects has successfully prevented delinquency. After briefly examining the results of previous projects, the authors discuss a series of nine recom mendations for future projects. These recommendations include separa tion of implementation and evaluation, enrichment or abandonment of the individual treatment approach, diversification of evaluative measures, and greater sensitivity to the rights of the juvenile subjects involved in future projects.