This paper reviews epidemiological estimates of criminal victimization derived largely from nationally based studies in the United States. Origins of conflicting rates and prevalences are explained in terms of varying methodology. Risk factors for victimization, including age, race, gender, and disability, are also outlined, and derived from both national and geographically limited U.S.-based studies. Finally, mental health outcomes of violence are documented, with conclusions drawing on both national and regionally specific studies. These outcomes focus on posttraumatic stress disorder, but also include depression, substance abuse, and panic.