DESCRIPTION: (Applicant's Abstract) Our recently completed randomized clinical trial of buprenorphine (BUP) at 12 mg daily in combination with desipramine (DMI) has shown superior efficacy to BUP alone and to methadone alone or in combination with DMI for opioid and cocaine abuse, and other work has shown excellent efficacy for a simple behavioral contingency using vouchers for drug free urines. This competing renewal therefore requests five years' support for a 24 week double blind, randomized clinical trial to test this combination of interventions. In this study 160 cocaine and opioid dependent patients maintained on BUP at 16 mg/70 kg will be assigned to four 40 patient cells: 1. DMI (150 mg) + contingencies, 2. placebo + Contingencies, 3. DMI + no Contingencies, 4. placebo + no Contingencies. For those in the contingency group, each drug-free urine submitted will result in a voucher worth a certain monetary value that increases for consecutively drug-free urines (weeks 1-12) or a monetary voucher with a fixed value under an increasing ratio of number of consecutive drug-free urines per voucher (weeks 13-24). Subjects not assigned to the contingency will receive monetary vouchers (weeks 1-24) according to a schedule that is not contingent upon illicit drug abstinence. Vouchers can be exchanged for mutually agreed upon goods and services at any time during the study. Outcome measures will include: 1) treatment retention, 2) illicit drug use, 3) self-reported adverse and opioid withdrawal symptoms, and 4) psychosocial functioning. Follow-up interviews at one year post-study entry will be conducted to determine status post-treatment. Prognostic factors (i.e., sex and depression), will also be examined in relation to treatment outcome and post-treatment status. We hypothesize that the combination of DMI + Contingencies will be more effective than either the contingencies alone or the DMI alone, and that depressives may respond best.