Narcotic addicts volunteered for treatment with methadone hydrochloride and cyclazocine in a community hospital. Eight of 15 addicts treated with methadone have been maintained in the community for more than one year, and their continued contact with the clinic provided a basis for habilitation. Cyclazocine, an experimental narcotic antagonist, was given to 103 patients. In 51, in a prolonged hospitalization "therapeutic community" program, cyclazocine did not augment their treatment. But, cyclazocine was successful in 52 additional patients treated rapidly and hospitalized for less than two months. After discharge, thirty-one attended a clinic three times weekly for two months. Four to 5 mg cyclazocine daily effectively blocked 15 mg intravenous heroin, up to 28 hours. Secondary effects of increased libido, euphoria, constipation, restlessness, and insomnia abated within two weeks. These results are promising, and cyclazocine is worthy of further investigation.