Analyzes the features of effective research-based violence-prevention programs and provides detailed guidance to schools implementing such programs. Developed by the University of Colorado-Boulder’s Center for the Study and Prevention, this guide describes (1) the criteria used for assessing the effectiveness of prevention or intervention programs; (2) a variety of model and promising programs, including those that involve changing the home environment through early childhood intervention and parent training, changing the school environment by establishing norms for behavior and instituting discipline and instructional management practices, changing the community environment, and focusing on individual needs through life-skills training and mentoring and tutoring; and (3) quality program delivery, assessment of site readiness, and challenges to program implementation. Recommendations include choosing a program that meets the needs of the target population, building an environment supportive of thenew program, ensuring that money, materials, and personnel are adequate, improving the quality of implementation, and developing materials for the program and the internal capacity to deliver it. Key factors contributing to a successful violence-prevention program include thorough, research-based planning, buy-in from all key staff, a strong and motivated program champion, and proactive and consistent training and technical assistance.