The transportability of Multisystemic Therapy (MST) for the treatment of juvenile offenders in a community-based context was examined in the current study. Results of this New Zealand study showed that significant pre- to posttreatment improvements occurred on most indicators of ultimate (i.e., offending behavior) and instrumental (i.e., youth compliance, family relations) treatment outcomes. Reductions in offending frequency and severity continued to improve across the 6- and 12-month follow-up intervals. In comparison to benchmarked studies, the current study demonstrated a more successful treatment completion rate. Additionally, overall treatment effect sizes were found to be clinically equivalent with the results of previous MST outcome studies with juvenile offenders and significantly greater than the effect sizes found in the control conditions. The findings of this evaluation add to the growing body of evidence that supports MST as an effective treatment for antisocial youth.