Contingency management (CM) is an empirically supported intervention for substance dependence, but it has not been evaluated systematically in non maintained opioid-dependent patients. This retrospective analysis examined whether CM was effective in opioid-dependent patients initiating intensive outpatient psychosocial treatment. In the primary trial (Petry, N. M., Weinstock, J., & Alessi, S. M. [2011]. A randomized trial of contingency management delivered in the context of group counseling. Journal of Consulting and Clinical Psychology, 79, 686–696), substance-abusing patients (n = 239) at two community-based clinics were randomized to standard care (SC) or SC with CM for 12 weeks; in the CM condition, patients earned opportunities to win prizes for attending treatment and submitting d…