The study found that most children aged 0 to 17 years old murdered each year in the United States were killed by persons unrelated to them, and there were apparently sizable numbers of young children (under 12 years old) who were assaulted by persons outside their families. When assault is defined more generally, as it is in this study, females are apparently at greater risk of nonfamily assault than are males. This finding is largely due to the inclusion of sexual assault in the definition of assault. For young children, there were ambiguous findings on the issue of child supervision and its relation to nonfamily child assault. On the one hand, parents of assaulted children were just as likely as other parents to report that they supervised their children fairly closely. Additionally, young children were typically assaulted in the course of their routine activities, and they were not in particularly dangerous places nor completely without adult supervision at the time of the assault. The lives of assaulted teenagers were marked by high levels of parent-child conflict compared to their non-assaulted counterparts. Conflict tended to center on issues of adolescent's choice of friends, their use of drugs, and their sexual behavior. For both younger and older victims of nonfamily assault, they were more likely to be living in households in which an adult was a victim of childhood trauma than was true for U.S. children in general. Recommendations encompass research and policy. 18 tables, 4 notes, and 36 references