['Contingency management (CM) interventions are efficacious in treating cocaine abusing methadone patients, but few studies have examined the effect of age on treatment outcomes in this population. This study evaluated the impact of age on treatment outcomes in cocaine abusing methadone patients.', 'Data were analyzed from 189 patients enrolled in one of three randomized studies that evaluated the efficacy of CM versus standard care (SC) treatment.', 'Age was associated with some demographics and drug use characteristics including racial composition, education, and methadone dose. Primary drug abuse treatment outcomes did not vary across age groups, but CM had a greater benefit for engendering longer durations of abstinence in the middle/older and older age groups compared to the younger age groups. At the 6-month follow-up, submission of a cocaine positive urine sample was predicted by submission of a cocaine positive sample at intake, higher methadone doses, and assignment to SC rather than CM treatment.'] Do older methadone patients achieve greater durations of cocaine abstinence with contingency management than younger patients?