This study evaluated the efficacy of three methods of training community mental health providers (N = 150) in Dialectical Behavior Therapy skills, including a written treatment manual; an interactive, multimedia online training (OLT); and a two-day instructor-led training workshop (ILT). A hybrid design was utilized that incorporated aspects of efficacy and effectiveness trials. Assessments were completed at baseline, post-training, and 30- and 90-days following training. The results indicate that learner satisfaction with the training was highest in OLT and ILT, and both resulted in significantly higher satisfaction ratings than the manual. OLT outperformed ILT and the manual in increasing knowledge of the treatment, whereas ILT and the manual did not differ. All three training methods resulted in comparable increases in clinicians' ability to apply course content in clinical simulations. Overall, the results provide strong support for the efficacy of technology-based OLT methods in disseminating knowledge of empirically supported treatments to community mental health providers, suggesting that OLT may be a high-quality, easily accessible, and affordable addition to traditional training methods.