The current study examined the efficacy of bullying prevention programs on preventing bullying behaviors and victimization in schools. We meta-analyzed 21 articles to determine the effectiveness of bullying prevention programs. Moderators were selected to assess various aspects of the programs. The moderators included grade level of program, parental involvement in program, outcome measurement method, and program focus. The results showed that bullying programs were more effective at reducing bullying and victimization at the middle school level compared to elementary school and high school. Including parents in the programs increased the success of preventing bullying. When studies used more than one method of collecting bullying data, the programs were shown to be more successful. A pro-social focus increased the success of the prevention programs. Implications of the study include understanding factors that contribute to bullying program success, and possible considerations for improving future programs.