In a retrospective study of 511 cases of alleged sexual abuse in children 12 years of age and under, data were analyzed with respect to the victim's age, sex, and the type of sexual abuse (intra- or extrafamilial). A total of 85.5% of the victims were female and 14.5% were male with ages ranging from 2 months to 12 years. The mean age of female victims was 6.8 years and that of male victims, 7.4 years. Most victims (68%) presented with histories of single assault by a known perpetrator (78%). Characteristics of abuse were found to be associated with the victim's age, sex, and relationship to the assailant. School-age victims were more likely to be abused by an individual outside the family or by a complete stranger. Older victims were also more likely to be involved in severe forms of sexual abuse (penetration, attempted penetration or oral-genital contact), associated with acts of abduction and with reports to the police. Male victims were more likely to be assaulted by a stranger, outside the home environment, and to suffer a more severe form of sexual abuse than female victims. Finally, extrafamilial sexual abuse was distinguished from intrafamilial sexual abuse insofar as it was more often a single episode, occurring outside the home environment, involving an act of abduction and physical force, and being reported to the police.