In 2007, the Washington State Department of Social and Health Services established the Thurston-Mason Children’s Mental Health Evidence-Based Practice Pilot Project (Pilot) to provide mental health services to children. The first evidence-based practice selected by the Pilot was Multisystemic Therapy (MST), an intensive family- and community-based treatment program for youth. Over a one-year follow-up period, the Institute examined criminal convictions of youth enrolled in the Pilot’s MST program. Compared to youth with similar criminal histories and demographic characteristics, MST youth were convicted of fewer crimes on average. Due to sample size, statistical significance was not attained in this evaluation of MST outcomes. The effect sizes observed, however, are within the expected range for MST according to other rigorous studies of that intervention and would likely return a net economic benefit to tax payers and crime victims.