To make sound health care decisions, policy makers, providers and researchers need access to relevant research findings. The role of systematic reviews is increasingly acknowledged as an important contribution in evidence-based health care decision making, and several review efforts, including that of the international Cochrane Collaboration, are under way. The Cochrane Collaborative Review Group on HIV Infection and AIDS (CRG on HIV/AIDS), conducts systematic reviews on the prevention and the treatment of HIV infection and AIDS and is guided by the Cochrane Collaboration's principles, which include minimizing potential bias, ensuring quality in the review process, keeping reviews up to date, and enhancing collaboration. The CDC HIV/AIDS Prevention Research Synthesis (PRS) project is working closely with the CRG on HIV/AIDS to produce Cochrane reviews of behavioral prevention interventions and on development and maintenance of a centralized, cumulative electronic database of HIV/AIDS behavioral prevention studies. Systematic reviews can play an important role in advancing evidence-based policy and practice in HIV/AIDS prevention and care.