This research was designed to compare data obtained from agency records at three treatment programs for juvenile male sex offenders with information available from clinicians once youth and their families had been in treatment for at least 6 months. Results revealed that over the course of treatment, youth and their families disclosed information about additional victims and offenses, physical and sexual abuse of the offenders, and several aspects of a violent and sexualized family environment. Over half the boys reported additional victims or additional offenses or both. There were significant increases in the number of reports of physical abuse, witnessing of domestic violence, living in a sexual environment, maternal sexual victimization, maternal victimization of domestic violence, and fathers being perpetrators of domestic violence. These data clearly support the hypotheses of the study and have important implications for both clinical practice and future research in this area.