Multisystemic Therapy (MST) for juvenile offenders addresses the multidimensional nature of behavior problems in troubled youth. Treatment focuses on those factors in each youth's social network that are contributing to his or her antisocial behavior. MST is delivered in the natural environment (in the home, school, or community). The typical duration of home-based MST services is approximately 4 months, with multiple therapist-family contacts occurring weekly. MST addresses risk factors in an individualized, comprehensive, and integrated fashion, allowing families to enhance protective factors. Specific treatment techniques used to facilitate these gains are based on empirically supported therapies, including behavioral, cognitive behavioral, and pragmatic family therapies.

The ultimate goal of MST is to empower families to build a healthier environment through the mobilization of existing child, family, and community resources.

Compared to youth receiving usual-treatment services, those receiving MST were arrested about half as often in the post-treatment period. Recidivism rates were significantly less for MST-treated youth. Youth who received MST also had an average of 73 fewer days of incarceration.

This intervention or an adaptation of this intervention has been described in more than 200 published articles, and a number of independent replications have been conducted. Study results include the following:

Compared to youth receiving usual-treatment services, youth receiving MST were arrested about half as often in the post-treatment period, F(1, 82) = 3.9, p < 0.05. Recidivism rates were 42% for the MST-treated youth compared to 62% for youth receiving the usual services. In a second study, MST was more effective than individual therapy in preventing rearrests for violent offenses during the follow-up period, F(2, 173) = 11.7, p < 0.001. At the end of 4 years of follow-up, the rate of criminal recidivism (rearrest) for the MST completers (22%) was less than one third the overall rate for IT completers (71%). At 13.7 years of follow-up, youth who received MST (then aged 29 years) showed significantly lower rates of criminal recidivism (50%) compared to the control group (81%), chi-squared (1, N = 176) = 18.5, p < 0.0001.

Youth who received MST had an average of 73 fewer days of incarceration than youth receiving usual services, F (1, 54) = 7.7, p < 0.006. More than two thirds (68%) of youth in the usual-services group were incarcerated after treatment compared to only 20% of the MST group. Almost 14 years after treatment, MST youth were sentenced to fewer than half as many days of incarceration as the comparison youth, chi-squared (1, N = 165) = 8.97, p < 0.01.

Posttreatment reports of alcohol and marijuana use and other drug use were less frequent among MST participants (p < 0.05). Posttreatment assessments also showed that family cohesion increased among families receiving MST (p < 0.05). Furthermore, reports of aggression with peers decreased significantly for MST participants (p < 0.05).