In brief: Millions of US children participate in recreational activities, organized youth leagues, and interscholastic sports programs. Although they enjoy and obtain health benefits from these activities, 3% to 11% of these children are injured while participating in sports programs each year. Epidemiologic studies show that different sports pose different types and degrees of risk and that injuries among children differ from those among adolescents. An awareness of injury patterns in youth sports helps physicians and others who care for children to identify variables associated with injury. Measures must be taken in all youth sports programs to modify such variables in an effort to prevent injuries.