A survey of smoking habits of medical students was done using basic medical science graduate students at the same institution as a comparison group. Smoking status was not significantly related to sex, race, or academic classification. Knowledge of adverse health consequences of smoking was related to time spent in medical school and to whether or not the respondent smoked (ie. probable denial of knowledge of the adverse consequences among smokers). The respondent's smoking status was significantly related to familial and peer group smoking status and to peer group attitude. The most common reason given by quitters was "the media influence." The nonsmoker most frequently never began the habit because of fear of health consequences. Because of the finding that a small percentage of medical students still are not convinced of the dangers of smoking, it was suggested that increased educational emphasis on these dangers be included in the medical curriculum.