Firearm violence is a serious threat to the health of our children: an American child dies of gunshot wounds every 1 1/2 hours, and every 2 days 30 children--the equivalent of a school classroom--lose their lives to guns. Injured children and adolescents are cared for in emergency departments and trauma centers, and in some urban areas the increasing incidence of firearm injuries threatens to overwhelm the trauma care delivery system. Because of the prevalence and enormous cost of firearm violence it has been identified as an epidemic and a public health emergency. In this article we discuss the burden of firearm injury and its effect on children and young adult, and we outline a public health approach to firearm injury prevention.