Information was obtained from responses to self-administered questionnaires completed by 758 male students in 10 inner-city high schools in the spring of 1991. The data pertain to firearms possession and carrying; use of heroin, cocaine, and crack; the sale of drugs; and commission of crimes with weapons. The findings provide no evidence of a progressive, linear relationship between level of drug use and gun possession, including number of guns owned and the routine carrying of guns; however, disregarding the level of drug use, when nonusers were compared with users and "heavy" users were compared with those who did not use drugs "heavily," significant differences in involvement in gun possession were found. Also, when the analysis separated students who did not sell drugs from those who did, the latter generally exhibited higher involvement in gun possession. Finally, drug sellers who also committed crimes with weapons exceeded drug sellers who did not in involvement in some types of gun possession. 6 tables and 49 references