This study assesses the outcomes of group intervention program with violent juveniles. The intervention is based on the ecological approach of Edleson and Tolman (1992). Forty-eight juveniles referred to the juvenile probation service because of violent crime completed the 16 sessions of the intervention. Participants completed questionnaires addressing their attitudes toward violence, perpetration of violent behavior toward others, and sociodemographic factors, pregroup and postgroup intervention. The results show significant reductions in juveniles' endorsement of violent behavior and in violence toward others. These reductions remained significant among the 27 juveniles who completed the 6-month follow-up. The discussion highlights the need for evaluation process among intervention programs conducted by social workers and recommends further research in the field.