Drawing on theoretical and empirical studies, this paper hypothesized that attitudes towards the use of violence and the use of aggressive and violent behavior among preadolescent African American males would be affected by verbal aggression in the home, violence observed in the community, family environment, and peer models. Data on aggressive and violent behavior and attitudes among young African American males were available from a larger project designed to improve self-esteem, decision skills, and interpersonal competence, and encourage positive attitudes toward non-European cultures. A data set with ratings from behavior and protective factors was obtained for 152 boys aged 8 to 13. Ratings came from 85 group leaders over 3 project years. A consistent finding from the three analyses performed was that attitudes toward the use of violent and aggressive behavior and actual use of violence and aggressive behavior seems to increase with age, with the effect being stronger for attitudes than actual behavior. One analysis suggested no correspondence in the boys' actual attitudes and behaviors and the way they behaved in the after school groups, suggesting that the use of violent and aggressive behavior is context specific. Ratings by group leaders were not affected by family environment, exposure to violence in the community, peer relationships, or age. Findings from a second analysis strongly support an ecological-developmental perspective, as all factors except positive peer relationships had a highly significant impact on self-control. Family structure improved self-control, family arguments decreased self-control, and exposure to community violence decreased self-control. Peers, exposure to community violence, and family arguments significantly affected the boys' actual use of aggressive and violent behavior. The boys lived in five different areas of the city, suggesting that socialization in any single neighborhood was not responsible. Multivariate analyses reveal that the most important factors affecting self-control were family arguments and age, while the most important factors affecting aggressive and violent behavior were peer relationships and family arguments. The findings suggest that programs designed to reduce violent behavior may be more effective if they include parents. An appendix describes the measures used in the study. (Contains 4 tables and 14 references.) (SLD)