A randomized study is planned over 5 years to evaluate the effectiveness of the Therapeutic Workplace in promoting naltrexone adherence in opiate-dependent adults. An extended-release depot formulation of naltrexone will be used. Participants will be offered an inpatient opioid detoxification and naltrexone induction. Participants who complete the oral naltrexone induction (N=80) will be randomly assigned to one of two groups. Both groups will be invited to work in the Therapeutic Workplace and will be prescribed depot naltrexone for 6 months. Patients in the "Work Plus Naltrexone Contingency" condition will earn access to working and earning salary by taking depot naltrexone once per month. "Work Plus Naltrexone Prescription" participants will be encouraged to take depot naltrexone monthly, but access to working and earning salary will not be contingent on doing so.