The Guide to Community Preventive Services (Community Guide) is being developed under the leadership of the independent, nonfederal Task Force on Community Preventive Services. The Task Force makes recommendations for the use of public health programs and policies based on scientific evidence about what practices have worked to improve health. The Community Guide thoroughly searches scientific literature for topic-relevant studies, evaluates their quality according to established criteria, and makes recommendations based on the overall strength of the body of evidence and the size and variability of reported effects. In addition, the Community Guide identifies promising interventions that have not been adequately researched, thus helping to inform the public health research agenda. The continuously updated and expanded body of recommendations and research agenda formulated by this rigorous process have been published on the Internet and in various publications since 1999 and constitute a highly valued and objective evidence-based resource for guiding current and future public health activities. More remains to be learned, however, on how best to disseminate Community Guide findings to key target audiences and encourage their use to inform practice, policy, and additional research.