The campuswide survey involved a random sample of 233 students (122 males and 111 females). Ten undergraduate classes were selected by the lottery method, and professors were contacted for permission to administer the questionnaire. The questionnaire consisted of 29 questions designed to determine the smoking habits of college students (median age of 21). Of the students completing the questionnaire, 60.4 percent reported having even smoked marijuana, and 41 percent reported smoking marijuana in the past month. Past-month cigarette smoking was reported by 4 percent of the students. Seventy-three percent of the students smoked marijuana before ever smoking cigarettes, or they began smoking both tobacco and marijuana simultaneously. Students reportedly smoked marijuana initially instead of cigarettes because they believed that cigarettes were "dangerous." Students believed marijuana to be safe. Students stated they smoked both substances for the synergistic and related effects, depending on the current environment and the various motivations for smoking. The identified progression from marijuana to cigarettes is a reversal of the traditional "gateway" theory of progression from tobacco smoking to marijuana smoking. Concurrent use of marijuana and tobacco by college students has apparently increased in popularity over the past decade. These findings suggest that the focus of anti-tobacco campaigns should include all smoking behavior, specifically marijuana smoking. Preventing the process of learning how to smoke should be a primary goal of future prevention efforts. 4 tables, 2 figures, and 22 references