Epidemiologic surveillance for the prevention and control of urban violence Violence prevention policies should be based on information, follow-up, research, and analysis, all of which increase the chances of success and make it easier to evaluate interventions. This implies, in turn, that there is a need to create surveillance, research, and prevention models for violence within the sphere of public health and epidemiology, a task that constitutes an integral part of the Pan American Health Organization’s Regional Plan of Action Health and Violence. This article describes the objectives of epidemiologic surveillance systems and explains their purpose and scope, along with the barriers that stand in the way of their implementation. It also examines a number of variables and their definitions, the types of analyses and reports that should be generated, and the decisions that can be made on the basis of these reports. Finally, it discusses ethical criteria and describes the experiences of the program known as Desarrollo, Seguridad y Paz (DESEPAZ) in Cali and Santa Fe de Bogota, Colombia, where an epidemiologic surveillance system against violence has been implemented.