Both MBRP and ED participants will be assessed at baseline, treatment-end, and 1 month post-treatment. 2) To test the impact of MBRP compared to ED on negative affect, stimulant use, and health care outcomes. 3) To evaluate the differential effects of MBRP versus ED on HIV-risk behavior of participants, and 4) To examine potential mechanisms of action of MBRP, including reductions in stress reactivity and biological indicators of arousal such as blood pressure and heart rate. The investigators hypothesize that MBRP will be more efficacious than ED in reducing negative affect and stimulant use. Further, the investigators expect that MBRP will produce greater reductions in HIV-risk behaviors, stress reactivity, and arousal, and these changes will be associated with substance use outcomes. MBRP incorporates specific substance-focused cognitive therapy techniques with an additional emphasis on mindfulness skills. By providing coping skills to address affect regulation and stress reactivity, two important factors in stimulant relapse, MBRP may provide a promising augmenting strategy for the treatment of stimulant users.
