Little is known about sexual perpetration by females or by young children. This paper describes the sexual perpetration behavior of 13 female child perpetrators between 4 and 13 years of age. These children were treated in a specially designed program for child perpetrators, the Support Program for Abuse-Reactive Kids (SPARK) at Children's Institute International of Los Angeles, California. All of these girls used force or coercion to gain the compliance of the other child or children. Of these child perpetrators, 100% had been previously sexually abused; 31% had been physically abused; 85% were molested by family members; 77% of the girls chose a victim in their family (the other 3 girls had no available family members). The mean age of their first known perpetration was 6 years, 9 months. The average age of their victims was 4 years, 4 months. The average number of victims of these girls was 3.5 with a range of 1 to 15. The girls victimized two times more boys than girls. There was a history of sexual, physical, and substance abuse in the families of these children. Hypotheses regarding the genesis of the sexually abusive behavior in these female child perpetrators are explored.