Background: Multiple approaches exist, both in theory and in practice, to reduce young people's risk of violent victimization when they are in school. Among these approaches, a growing number of school districts are choosing to install metal detectors. We sought to review the literature available on the impacts of metal detectors on school violence and perceptions about school violence. Methods: We conducted an extensive literature search, including databases for the medical, public health, sociology, and political science literature. Of 128 papers that met our search criteria, 7 studies met inclusion criteria for the literature review. Results: Each of the papers reviewed utilized data that originated from self-report surveys. Four of the studies consisted of secondary analyses of national databases, with the other 3 utilizing local surveys. The studies varied as to the outcome, ranging from student/staff perceptions of safety at school to student self-reports of weapon carrying and/or victimization, and showed mixed results. Several studies suggested potential detrimental effects of metal detectors on student perceptions of safety. One study showed a significant beneficial effect, linking metal detector use to a decrease in the likelihood that students reported carrying a weapon while in school (7.8% vs 13.8%), without a change in weapon carrying in other settings or a decline in participation in physical fights. Conclusion: There is insufficient data in the literature to determine whether the presence of metal detectors in schools reduces the risk of violent behavior among students, and some research suggests that the presence of metal detectors may detrimentally impact student perceptions of safety. (Contains 1 table.)