Effective interventions for drug abusing adolescents are underutilized. Using an interrupted time series design, this study tested a multicomponent, multi-level technology transfer intervention developed to train clinical staff within an existing day treatment program to implement multidimensional family therapy (MDFT), an evidence-based adolescent substance abuse treatment. The sample included 10 program staff and 104 clients. MDFT was incorporated into the program and changes were noted in the program environment, therapist behavior, and in most (e.g., drug abstinence, and out of home placements) but not all (e.g., drug use frequency) client outcomes. These changes remained after MDFT supervision was withdrawn.