The purpose of this study is to elucidate the use of formative research to adapt, develop, and pretest a mindful yoga curriculum for high-risk youth attending a nontraditional high school. The formative work was conducted in the first year of a larger project to test the efficacy of a mindful yoga program through a randomized controlled trial. The formative work included focus groups with: (1) an Advisory Board of experts in preventive interventions with high-risk youth, yoga and mindfulness and (2) students in the target population. Major themes emerging from the Advisory Board included youths' preconceptions about yoga, desirable characteristics in a yoga teacher, racial/ethnic differences in yoga participation, gender differences, and youths' likely motivations for participation. Additional themes reported by the student focus group participants included perceived motivations for participation, likely benefits of yoga, perceptions of yoga, yoga experience, and peer opinions. Additional results pertained to important logistical considerations when implementing school-based yoga programs. The formative work resulted in a 20-session, manualized curriculum that was pretested with students. Pretesting indicated that the intervention was feasible and enjoyable. In a focus group following the intervention, students reported improved mood and a high degree of satisfaction with the intervention. Implementation challenges included logistics within a school setting, recruitment and consenting, gender considerations, and developmental issues.