The information was collected in interviews conducted by a staff psychologist shortly after each inmate's arrival. Forty-two percent of the participants acknowledged a prior history of drug misuse, which was minimally defined as the weekly ingestion of a psychoactive substance for a period of 3 or more months. A total of 57.4 percent of the participants reported that they were abstinent due only to incarceration, 24.8 percent reported that they stopped using drugs on their own without treatment. Participants who continued using drugs or desisted only because of incarceration differed from those who displayed spontaneous remission. One interpretation of this finding is that participants in the spontaneous remission group perceived themselves as having experienced significantly fewer problems as a consequence of drug use than did participants in the other groups. Tables and 24 references (Author abstract modified)