The primary goal of WINGS was to reduce the number of girls entering or continuing in the juvenile justice system by supporting and empowering them and their families to access and receive appropriate services. Using a classic experimental design, this assessment tracked the girls’ progress in the program, documented the interventions, and determined outcomes, including recidivism. Between April and December 2000, 499 eligible girls were randomized to either participate in WINGS or to received treatment as usual and serve as the comparison group. Starting in January 2001, another 299 girls were randomized into a second sample. Results for the evaluation support the view that providing services that were family-focused, gender-responsive, center-based, and included home visits was beneficial to program participants. Clients represented a variety of ethnic groups and came to the program for different reasons, but shared a history of having experienced traumatic events in their lives. A number of factors were related to program completion, including having prosocial relationships, valuing fairness and honesty, and having constructive outlets. Clients in the second sample were more likely to become engaged and completed the program in a shorter amount of time, supporting the view that WINGS matured over time. Clients received a variety of services, including crisis intervention, girls’ group, life skills, conflict resolution, and health education. Impact evaluation findings showed that successful clients had significantly more protective factors and fewer risk factors at exit. While this change in resiliency was associated with positive changes in school engagement, it was not directly tied to lower recidivism rates. Recommendations for implementation in other counties include identifying local service gaps prior to program implementation so that the program is most effective in meeting regional needs; and securing flexible funding for all program components to ensure that the basic needs of clients can be met. 9 tables, 33 figures, 21 references