Substance Use and HIV Prevention Program (SHIP) is a school-based intervention model designed to reverse detrimental trajectories in nonsexual (i.e., substance use) and sexual behaviors by adapting two research-supported interventions: Reconnecting Youth and Street Smart. The Social Development Model provides the theoretical and conceptual basis. The model targets two health indicators known to impede healthy functioning among adolescents: substance use and HIV risk behaviors. The target population is juvenile offenders who attend alternative high schools and who present a constellation of at-risk behaviors that include substance use, risky sexual behavior, gang affiliation, violent and nonviolent offenses, juvenile delinquency, high school expulsion, and poor school attendance. The needs of these juvenile offenders are best addressed through intensive multi-component classroom-delivered interventions. (Contains 2 tables.)