The RAND Corporation's Gun Policy in America initiative is a unique attempt to systematically and transparently assess available scientific evidence on the real effects of gun laws and policies. Our goal is to create resources where policymakers and the general public can access unbiased information that informs and enables the development of fair and effective policies. Good gun policies in the United States require consideration of many factors, including the law and constitutional rights, the interests of various stakeholder groups, and information about the likely effects of different policies on a range of outcomes. This report seeks to provide the third factor—objective information about what the scientific literature examining gun policies can tell us about the likely effects of those policies. This report synthesizes the available scientific evidence on the effects of various gun policies on firearm deaths, violent crime, the gun industry, participation in hunting and sport shooting, and other outcomes.1 It builds and expands on earlier comprehensive reviews of scientific evidence on gun policy conducted more than a decade ago by the National Research Council (NRC) (see NRC, 2004) and the Community Preventive Services Task Force (see Hahn et al., 2005).