Given the prevalence of the misuse of various substances within the United Kingdom population, the level of training for medical undergraduates in this field remains scant. The current study was designed to probe whether medical students in the United Kingdom held discriminatory attitudes or other strong beliefs regarding substance misusers. The study also investigated how aware current medical students were about substance misuse. Participants were 671 students within their first and fourth year of medical school who completed a questionnaire probing knowledge, attitudes to training, clinical practice, and stigma. Results indicated a low level of knowledge among the students regarding substance misuse, with little improvement observed between the first and fourth years of study. Attitudes toward training were positive and clinical experience with substance misusers increased between years 1 and 4 of medical school. Negative attitudes decreased with increased clinical experience, although overall a large proportion of the students held negative attitudes about substance misusers. The findings underscore the importance of substance misuse training for medical students. Future studies should focus on the views of nurses as important members of interdisciplinary medical teams. Tables, figure, appendix, references