Crime-prevention research has consistently found that rates of interpersonal violence can be significantly reduced through well-planned, multisector strategies that address multiple causes. Although there is no definitive analysis that has produced an exhaustive list of crime causes, the United Nations Congresses concur with the scientific literature in concluding that crime causes are multiple and involve social-development, cultural, situational, and law-enforcement factors. International norms for crime prevention strategies require appropriate responses from all levels of government and civil society. Cooperation between government and private sectors ensures appropriate legislation, funding, organizational capacity, and the active participation of communities and nongovernmental organizations. Seven international norms for crime prevention are listed. First, crime prevention requires systematic analysis, planning, implementation, and evaluation. Second, it requires knowledge-driven strategies with appropriate staffing and data systems. Third, multisector partnerships are required to address the multiple social factors linked to crime. Fourth, there should be comprehensive strategies that target high-risk neighborhoods and involve environmental design. Fifth, there must be local prevention strategies that reduce opportunities for transnational crime. Sixth, public participation and outreach is essential; and seventh, there should be a permanent and funded center that is responsible for crime prevention. Crime-prevention strategies implemented in various countries are presented to show how the application of the aforementioned principles has been effective in reducing crime. 5 figures and 24 references