This study examines the problems and prospects of aftercare of the multiple treatment failure opiate addict who is being treated with narcotic antagonists (primarily naltrexone). At the time of this paper, 21 patients had been admitted to the Drug Addiction Research Project at McLean Hospital, with a retention rate of 42%. "Completers," "noncompleters," and "dropouts" could not be differentiated on the basis of demographic or psychiatric variables, thus making it impossible to define the population most suited for antagonist treatment. The degree of carry-over into the first month in the community, for those who successfully completed the inpatient segment of the program, disappeared over time. The nonreinforcing (lack of euphoric effect) properties of the antagonists and the resultant high level of motivation necessary for the continuation of its use by the patient make this form of treatment suitable for only a small percentage of the "hard core" addict population.