The Sex Offender Treatment Program has two components: the Sex Offender Treatment Unit, which is a residential treatment unit located in a separate wing of the facility; and the Sex Offender Unit, which is an aftercare component for sex offenders who are eventually paroled to Cook County. Individual treatment elements include initial assessments by mental health professionals; sex-offender-specific treatment, including group therapy and written assignments, individual counseling, violence interruption process groups, and didactic sessions on sex education and substance abuse; structured leisure time activities; and unstructured recreation. These findings from the second-year evaluation focused on the continuing implementation of the sex offender program, the process evaluation, and preliminary outcome data. The impact of the juvenile justice system on offenders in the treatment program was evaluated in terms of the preservation of public safety and the improvement in interagency and intra-agency communication. The program apparently contributed to public safety by increasing the range of services available to sex offenders and by heightening the intensity of supervision received by juvenile sex offenders paroled to Cook County. In determining program impacts, the evaluation examined whether or not program staff identified offenders who were appropriate for the program. It also determined whether program staff properly assessed offenders for treatment needs. Further, the evaluation of program impact examined whether the treatment needs identified were met through the programming provided. The evaluation assessed the individual impact of the program by determining the extent to which the participating youths experienced behavioral changes. Interviews conducted suggested that participants were more in control of their behavior and were more willing to engage in discussion after several months of treatment. Recommendations focus on the documentation of needs and changes in participants, the linking of activities and assignments to treatment goals, revising treatment manuals to take into account individual differences in participants, the documentation of program changes, and the use of contractual consultants to enhance services and coordination. 2 tables