An overview of the effectiveness and efficiency of HIV prevention programs.

Because of the enormity of the HIV-AIDS epidemic and the urgency for preventing transmission, HIV prevention programs are a high priority for careful and timely evaluations. Information on program effectiveness and efficiency is needed for decision-making about future HIV prevention priorities. General characteristics of successful HIV prevention programs, programs empirically evaluated and found to change (or not change) high-risk behaviors or in need of further empirical study, and economic evaluations of certain programs are described and summarized with attention limited to programs that have a behavioral basis. HIV prevention programs have an impact on averting or reducing risk behaviors, particularly when they are delivered with sufficient resources, intensity, and cultural competency and are based on a firm foundation of behavioral and social science theory and past research. Economic evaluations have found that some of these behaviorally based programs yield net economic benefits to society, and others are likely cost-effective (even if not cost-saving) relative to other health programs. Still, specific improvements should be made in certain HIV prevention programs.