Five percent of deaths of persons under 18 are homicides, compared to 1 percent for people over 18. In addition, homicide is the only leading cause of death for children under 15 that has increased in incidence in the last 30 years. Preventive efforts focusing on deterring perpetrators require the determination of their social and psychological characteristics, while efforts focusing on protecting potential victims require the identification of situations that make children vulnerable to injury. Existing research shows that the highest rates of child homicide are in infancy and that age-inappropriate expectations lead some adults to dangerously severe punishment of young children. Little is known about how many victims' families have been involved with child protection or child welfare agencies, however. Nevertheless, recent studies indicate that chance factors determine whether a child abuse or neglect episode will be fatal, suggesting that prevention of child homicide requires prevention of all child abuse. Tables and 31 references.