As the public health threat of childhood obesity has become clear, the issue has become the focus of local, state, and national initiatives. Many of these efforts are centered on the community environment in recognition of the role of environmental factors in individual behaviors related to food and physical activity. In many communities, for example, fresh produce is not available or affordable, streets and parks are not amenable to exercise, and policies and economic choices make fast food cheaper and more convenient than healthier alternatives. Community efforts to combat obesity vary in scope and scale; overall, however, they remain fragmented, and little is known about their effectiveness. At the local level, communities are struggling to determine which obesity prevention programs to initiate and how to evaluate their impact. In this context, the Institute of Medicine held two workshops to inform current work on obesity prevention in children through input from individuals who are actively engaged in community- and policy-based obesity prevention programs. Community perspectives were elicited on the challenges involved in undertaking policy and programmatic interventions aimed at preventing childhood obesity, and on approaches to program implementation and evaluation that have shown promise. Highlights of the workshop presentations and discussions are presented in this volume. Table of ContentsFront MatterSUMMARY OF WORKSHOP--June 20081 Introduction2 Perspectives of Evaluators3 Perspectives of Site LeadersReferencesSUMMARY OF WORKSHOP 2--May 2009Summary4 Introduction5 Community-Based Programs: How Does Information Help Them AchieveTheir Goals?6 Research and Advocacy Groups: How Does Evidence Inform Policy?7 Decision Makers: How Do Community Perspectives Influence Policy?8 Closing RemarksReferencesAppendix A: Workshop AgendasAppendix B: Biographical SketchesAppendix C: Workshop Attendees