OBJECTIVES: Increasing evidence demonstrates effectiveness of Mindfulness-Based Stress Reduction (MBSR) for pain-related and functional disorders. In order to conduct successful and efficient trials of MBSR, evidence regarding the relative performance of strategies to improve recruitment, retention, and adherence is required, but few studies have examined these issues specifically. DESIGN: In preparation for a fully powered trial, we conducted a 2-arm, parallel comparison randomized controlled feasibility trial of MBSR vs. usual-care for 60 patients with migraine headache. SETTING: Two large U.S. health systems in Northern California. INTERVENTION: MBSR is an 8-week classroom-based intervention that combines mindfulness meditation and yoga, with didactic presentations about stress psychology and group process/experiential education. Participants received the intervention at their choice of one of several existing, vetted community-based classes. MAIN OUTCOME MEASURES: Successful recruitment was defined a priori as 18 participants within any 9-week period or 60 participants enrolled within a 36-week period. We considered participants adherent to the intervention if they attended at least 5 of the 8 weekly classes and the day-long retreat. RESULTS: We successfully enrolled 18 participants within a 7-week period, however, we did not attain our second goal of recruiting 60 participants within a 36-week period. Sixty-eight percent of our participants were adherent to the intervention. CONCLUSIONS: We found that close monitoring of recruitment activities, flexibility in protocol modifications, and integration within the delivery system were crucial factors for successful participant recruitment, retention, and adherence in mindfulness research.