This study evaluated the efficacy of methods of training community mental health providers (N=132) in dialectical behavior therapy (DBT) distress tolerance skills, including (a) Linehan's (1993a) Skills Training Manual for Borderline Personality Disorder (Manual), (b) a multimedia e-Learning course covering the same content (e-DBT), and (c) a placebo control e-Learning course (e-Control). Participants were randomized to a condition, and the training took place in a highly structured and controlled learning environment. Assessments were completed at baseline, post-training, and 2, 7, 11, and 15 weeks following training. The results indicate that one or both of the active DBT conditions outperformed the control condition on all outcomes except motivation to learn and use the treatment. While clinicians preferred e-DBT over the Manual and found it more helpful and engaging, the active DBT conditions generally did not differ on the primary outcomes of knowledge and self-efficacy, with the exception that e-DBT significantly outperformed the Manual on knowledge at the 15-week follow-up. E-DBT also produced the highest rate of applying and teaching the newly learned skills in clinical practice. Overall, results from this study support the efficacy of e-Learning in disseminating knowledge of empirically supported treatments to clinicians, while also indicating that treatment manuals can be effective training tools.