Background: Professionalism is comprised of a set of values and behaviours that underpin the social contract between the public and the medical profession. Medical errors are reported to result in significant morbidity and mortality and are in-part related to underdeveloped professionalism. Aims: The aim was to determine whether specific aspects of professionalism were underdeveloped in medical students. Method: A questionnaire with 24 vignettes was taken by Year 2, 4, and 6 medical students and their responses were compared to responses from practicing Medical Academics. Results: Second, fourth and sixth Year medical students' responses differed from Academics in two aspects of professionalism, firstly, high ethical and moral standards and secondly, humanistic values such as integrity and honesty. Only Year 2 medical students' responses were different from Academics when it came to responsibility and accountability. Conclusions: Certain aspects of professionalism seem to be underdeveloped in medical students. These aspects of professionalism may need to be targeted for teaching and assessment in order that students develop as professionally responsible practitioners. In turn, students with well-developed professionalism may be less involved in medical error, and if involved they may have the personal values which can help them deal with error more honestly and effectively.