Medical students at the University of Edinburgh in Scotland can volunteer to participate in an undergraduate options project that gives them the opportunity to provide sex education for secondary school (high school) pupils. Using a questionnaire presenting a set of fictional case histories, we assessed medical students' theoretical confidence at dealing with sexual health consultations. Students who had participated in delivering peer-led sex education felt significantly more confident at discussing sexual health issues with patients of all age groups (p = 0.001) than students who had not participated in the project. All students felt more comfortable seeing patients of the same gender as themselves but more than half felt that their training left them generally ill-equipped to handle sexual health consultations.