The sample consisted of 200 persons attending a drug pretreatment counseling center over a 13-month period. The findings showed that heavy and moderate drug users had more drug-abusing friends than light and experimental users. They also met frequently with those friends to use drugs and to exchange information about is selling and buying illicit drugs. Heavy drug users tended to commit both predatory and nonpredatory crimes with their drug- abusing friends; light and experimental drug users were less likely to engage in criminal activity. The evidence suggests that association with drug-abusing peers is a strong predictor of a person's own drug abuse behavior. 7 references