• Violence, including homicide, child abuse and neglect, and assault by peers and others, causes over 2000 deaths a year to US children aged 0 to 19 years. Homicide is a leading cause of death for US children and adolescents, and so a major cause of years of potential life lost. Infantile and adolescent patterns of homicide are recognized: child abuse by parents characterizes the former; gunshots and other assaults by peers characterize the latter. Nonfatal violent injury is far more prevalent than the fatalities. Reliable estimates indicate that each year close to 1 million female adolescents are sexually assaulted, and more than 1.5 million children and adolescents are abused by the adults responsible for them. Adolescents experience violent crimes at extremely high rates. Risk factors for violent injury are recognized. The most consistent include male sex (except for sexual abuse) and urban residence. Despite the toll of violence, surprisingly little is known about its origins and means to prevent it. The only prevention approach that has been both well evaluated and of apparent benefit is the home health visitor for prevention of child abuse in infants of young, impoverished, unmarried primiparous women. Many other approaches are plausible, promising, and/or being implemented, and these require thorough trial and evaluation. Research on numerous aspects of the precursors and correlates of violence against children is also needed.