Antisocial behavior among youth remains a serious personal and social problem in the United States. The purposes of this study were to (1) identify the shape and number of developmental trajectories of antisocial behavior in a sample of poor, inner-city African American youth, and (2) test predictors of group membership and the developmental course of antisocial behaviors. Using growth mixture modeling, we examined predictors of antisocial behavior pathways and the likelihood of arrest in a sample of 566 poor, urban African American adolescents (ages 11 to 16). Three distinct trajectory classes of antisocial behavior were identified over a period of six years: one low-risk group (low steady) and two high-risk groups (incremental and high starter). The conditional probabilities for being arrested during ages 14-16 were 0.18 for the low steady class, 0.68 for the incremental class, and 0.31 for high starter class. Prevention strategies for adolescents at high risk are discussed.