According to social learning theory, drug users should be distinguishable from nonusers not only in terms of their drug-using behavior but also in drug users' pro-drug peer associations, orientations, and outlooks. The dependent variable in this study was the use of illicit or controlled substances (focus on nonalcoholic drugs). Two sets of independent variables were used in the analysis: personal-biographical and social-learning variables. In the grouped cases, 93 percent of the nonusers and current users wer correctly classified by using the personal-biographical and social-learning variables. The best single predictor of drug use and nonuse was the level of peer use of drugs, followed by differential peer definitions and personal approval. Adding the personal-biographical features yielded very little change in the relative impact of each of these social-learning variables. Social learning variables were not precise in differentiating between former users and nonusers. They were somewhat effective in distinguishing former users from current users. 5 tables and 31 references