This study compared the effects of 4 voucher incentive conditions of a brief abstinence test on continuous cocaine abstinence. In 3 conditions, cocaine-abusing methadone patients could earn $100 for 2 days of cocaine abstinence; 2 of these conditions offered, on either a continuous or interrupted schedule, an additional $300 for evidence of sustained abstinence over the next 9 days. In the 4th condition, no incentives were available. In incentive conditions, 70-80% of patients initiated abstinence, compared with 48% in the no-incentive condition. Both continuing reinforcement conditions produced higher rates of sustained abstinence than the single and no-voucher conditions. The study confirmed the utility of quantitative urine-testing methods combined with high valued incentives to promote cocaine abstinence initiation in methadone maintenance patients.