Objective: This study was designed to quantitatively evaluate the effectiveness of motivational interviewing (MI) interventions for adolescent substance use behavior change. Method: Literature searches of electronic databases were undertaken in addition to manual reference searches of identified review articles. Databases searched include PsycINFO, PUBMED/MEDLINE, and Educational Resources Information Center. Twenty-one independent studies, representing 5,471 participants, were located and analyzed. Results: An omnibus weighted mean effect size for all identified MI interventions revealed a small, but significant, posttreatment effect size (mean d = 0.173, 95% CI [0.094, 0.252], n = 21). Small, but significant, effect sizes were observed at follow-up suggesting that MI interventions for adolescent substance use retain their effect over time. MI interventions were effective across a variety of substance use behaviors, varying session lengths, and different settings, and for interventions that used clinicians with different levels of education. Conclusions: The effectiveness of MI interventions for adolescent substance use behavior change is supported by this meta-analytic review. In consideration of these results, as well as the larger literature, MI should be considered as a treatment for adolescent substance use. (Contains 2 tables, 1 footnote and 2 figures.)