This multi-site examination of sexual abuse histories of youth in residential treatment centers asked, for the sample as a whole and by youth's gender: (a) How many perpetrators did each youth have? (b) What was the gender of the perpetrator? (c) What proportion of youth was abused by family members? (d) What proportion of youth was abused in a child welfare setting? And, (e) what proportion of sexually abused youth were also victims of physical abuse and/or neglect? Results revealed that males were more likely to have one perpetrator, a female perpetrator, and to have been abused in a child welfare setting and less likely be abused by a family member. Implications for refining programs and practices are discussed. (Contains 7 tables.)