In this study the authors examined the influence of length of participation in a community-based reentry program on the odds of reconviction in the juvenile and adult criminal justice systems. A structured telephone survey of reentry program alumni was conducted with 75 transition-age (18-25 year-old) young men. Binary logistic regression analysis revealed that increased length of participation in reentry services decreased the likelihood of new convictions in the juvenile system, but not in the adult system. Lower education attainment, unemployment and older age were all associated with the odds of new convictions in the adult criminal justice system. Implications for reentry services include extended service length and a focus on educational and vocational opportunities. (Contains 5 tables.)