Objective To assess the undergraduate educational environment in a large UK medical school. Method Prospective study using the already validated Dundee Ready Education Environment (DREEM) questionnaire ( Appendix 1). Setting A large UK medical school. Participants All medical students enrolled in the academic year 2002/2003. Main outcome measures Perception of the overall educational environment. In addition the impact of year of study and gender were examined. Results The DREEM questionnaire consisting of 50 items scored on a 0-4 Likert scale was completed by 749 medical students (55 per cent) in the academic year 2002/2003. The mean total score was 124 (out of a maximum of 200) indicating relative satisfaction with the perceived environment. There were no individual areas of excellence (that is no item scored >3.5). Some items scored consistently badly indicating cause for concern, for example lack of a support system for stressed students, school time-tabling, feedback from teachers and memorisation of facts. Clinical students perceived the environment to be significantly more positive than preclinical students (127 v 119, p<0.05). Female students perceived the environment to be significantly more positive compared to male students (126 v 123, p<0.05). Conclusions This tool identified areas of concern within a large UK medical school. Further use of the DREEM as a monitoring tool would be useful to re-evaluate the environment following appropriate intervention.