['This study examined the impact of a low-cost contingency management (CM) delivered by program clinicians on treatment attendance and utilization for patients enrolled in outpatient psychosocial substance abuse treatment.', 'The study used a pre-posttest design to compare substance abuse patients who received Reinforcement-Based Treatment (RBT) plus low cost CM (n=130; RBT+CM) to patients who received RBT only (n=132, RBT). RBT+CM participants received a $10 incentive for returning to treatment the day following intake assessment (day one), and a $15 incentive for attending treatment on day five following admission. RBT clients received standard care intervention without the addition of the CM procedures. Groups were compared on proportion of participants who returned to treatment on day one, mean days of treatment attendance, individual sessions attended, and treatment utilization during the first week and the first month following treatment admission.', 'Both the RBT+CM and RBT group participants returned to the clinic on day one at high rates (95% versus 89%, respectively). However, the RBT group participants were more likely to attend the intake assessment only (i.e., never return to treatment) compared to the RBT+CM participants. Additionally, the RBT+CM participants attended significantly more treatment days, attended more individual counseling sessions, and had higher rates of overall treatment utilization compared to the RBT participants during the one week and one month following treatment admission.'] Does clinician-delivered contingency management increase engagement and attendance in drug and alcohol treatment?