Firearm injuries, by virtue of the number of deaths, years of life lost, and cost to society, represent an important and persistent public health problem. It is also a problem that crosses several disciplines, particularly public health, clinical medicine, mental health, criminology, and criminal justice. Approaches to controlling injuries due to guns involve all of these disciplines and include many strategies that have been effective for other injury control problems. In 2005, the U.S. Task Force on Community Preventive Services published a systematic review of gun laws and effects on homicide and suicide (Hahn et al., 2005). That review contains detailed tables about the effect of a variety of laws. The National Academies was recently asked to assess “the strengths and limitations of the existing research and data on gun violence.” Their report (National Research Council, 2005) provides another comprehensive review, with detailed tables, weighing the evidence for various interventions. Due to space constraints, neither document can be summarized here. The intended audience and the goals of these two reports differ from those of this chapter. The National Research Council (NRC) report was targeted at researchers, and its recommendations were directed at stimulating a stronger evidence base for gun policy through rigorous research. The Task Force report was narrowly focused on legislative approaches and, similar to the NRC report, was directed at assessing the quality of the current research evidence on gun policy. This chapter, on the other hand, is directed at public health practitioners and policy makers—individuals who must base their actions and decisions on the evidence that is available now.