Injuries and accidents are acknowledged as leading causes of mortality among children and adolescents in the developing countries of the world. However, little is known of the extent of non-fatal injuries and of their potential risk factors. The Pan American Health Organization sponsored the first collaborative study to examine morbidity incidence in specified areas of four selected countries in Latin America, and to test the feasibility and practicality of the developed methodology for application in other regions of the world. The study subjects were injured children and adolescents (0-19 years of age) presenting at the study hospitals in the chosen urban centres, as well as injured that were surveyed in households in the catchment area of the hospitals. Falls constituted the most common (40-52%) cause of injury in all areas, and tended to occur in the younger age groups. Motor vehicle injuries were not as frequent (5-24%) as expected from mortality studies. Males outnumbered females 2:1. The home was the most frequent (37-57%) site of injuries, especially for younger ages. Few received medical care at the site of the injury or en route to a hospital, if they went at all. The results found are consistent with those found in other studies in the developed world. The study methodology provides initial valid information for investigating the injury situation in countries with limited resources.