Studied semantic representations of drug terms as a function of reported use of illicit drugs, with young-adult industrial workers as the Ss (college students served in a preliminary study). Procedures for describing semantic organizations included the semantic differential, similarity ratings, sorting, and verbal production of drug names. In general, structured representations of drug terms were produced, in line with the categories: illicit drugs, medicinal drugs, alcohol products, and substances containing nicotine or caffeine. Increased drug use was accompanied by more positive evaluations of illicit drugs on the semantic differential and more extensive clustering on the verbal production task. It was concluded that use of illicit drugs is accompanied by distinctive semantic representations, that these patterns mainly involve drugs used illicitly, and that they are most apparent on tasks in which responses are least constrained, such as verbal production.