Using a variant of the ecological-transactional model and developmental theories of delinquency on a nationally representative sample of adolescents, the current study explored the ecological predictors of violent victimization, perpetration, and both for three different developmental stages during adolescence. We examined the relative influence of individual and family characteristics, peers, and neighborhood characteristics on the odds of experiencing violent victimization and perpetration over time with two waves of the National Longitudinal Study of Adolescent Health for those adolescents who reported no exposure to violence at Wave 1 (N = 8,267; 50 percent female; 59 percent Caucasian; 17 percent African-American; 14 percent Hispanic). We found that more proximal factors differentiated between different experiences with violence at Wave 2. Also, negative peers significantly differentiated between violent victimization and perpetration, and this influence was strongest in early adolescence. In exploratory analyses, we found that middle adolescents were particularly vulnerable to their disadvantaged neighborhoods for a high-risk group. This analysis is one of the few that considers multiple ecological contexts simultaneously and provides support for developmental differences within adolescence on the influence that peers and neighborhoods have in predicting violent victimization and perpetration. Tables and references (Published Abstract)