The results of this study show that gangs were present in the schools in the study, and that the presence of gangs was related to the violence in the school. The data also showed that antigang measures and strategies taken by the schools in the study were not effective in preventing gang activities on school premises. Basic descriptive statistics provide an overview of the data. Specifically, bivariate analyses focused on the relationships between the involvement in gangs, drug use, and gang membership and violence. The findings suggest that gang violence prevention necessitates that schools not only acknowledge the presence of gangs on their premises, but that they actively investigate the gangs, determine who the members are, what are their activities, and severely punish perpetrators who are involved in gang violence; that gang awareness training be implemented and focus on the organizational structures of schools; and that schools understand that gang prevention is multifaceted and requires long-term strategies. Data were collected from 325 respondents from 2 northeastern high schools using a questionnaire. Figures, tables, references