During a 3-week period in the fall of 1980, the 200 subjects completed the questionnaire, which was administered individually or in small groups. Three separate instruments comprised the questionnaire: a drug use inventory, a drug knowledge test, and a drug attitude scale. The drug use inventory measured past involvement with nine psychoactive drugs and one bogus drug, which permitted the investigators to monitor the reliability of subjects' self-reporting. Alcohol was reported as the most used drug, with marijuana ranked second and nicotine third. A majority of the subjects admitted to the illegal use of prescriptive drugs such as amphetamines and barbituates as well as the use of strictly controlled substances such as cocaine and narcotics. Drug-knowledgeable subjects tended to report greater drug involvement, and subjects with greater drug knowledge tended to be antagonistic toward personal drug use and drug use by others (antidrug); however, a significant negative relationship was found between drug practices and drug attitudes, meaning that those reporting limited past drug practices were likely to be against personal drug use and the use of drugs by others. The findings suggest that programmers in controlled environments might solicit the aid of older inmates in educating other inmates about drugs. The older inmates, who in this study had significantly higher drug knowledge and attitude scores (antidrug), could be trained to present more accurate drug knowledge than that acquired on the 'street.'