Two sets of findings resulted from this study. Regarding the impact of the therapy, the study found that multisystemic therapy (MST) was not effective in decreasing recidivism rates among juvenile delinquents released from an OCFS (Office of Children and Family Services) facility, and few subgroup differences in treatment were found across the four sample sites. Regarding implementation of the program, the study found that while OCFS's implementation of the program was unique, the services provided by the department adhered to the MST treatment principles and analytic model; the problems faced by the youth and families served by the MST program were multiple and severe; the recidivism rates were higher for youth when their families had mental health, criminal affiliation, and family conflict issues; and program outcomes were not associated with treatment duration or intensity but did vary with treatment content. This report examines the effectiveness of MST on the recidivism rates of youth who have been released from an OCFS facility. MST is a short-term, intensive treatment program that focuses primarily on environmental systems, with services provided in the family home or at community-based locations at times that are convenient for the youth and their families. A sample of 898 youth released from OCFS facilities between March, 2000, and May, 2004, were included in the study. The study was divided into two parts: to evaluate the effectiveness of MST on recidivism rates of youth recently released from an OCFS facility, and to examine the State's adherence to the principles of MST. Results of the study indicate that MST was ineffective for treating youth released from OCFS facilities for two reasons: the severity and intractability of the problems facing OCFS youth and their families, and the decision to use MST as a post-release service. Recommendations for future use of the program are discussed. Tables, figures, and references