Aims: To determine the prevalence and nature of prescription drug misuse among university staff and students in the UK. Methods: In 2009, an online questionnaire regarding non-medical use of prescription drugs was completed by 1614 students and 489 staff registered at a large university in Wales. The sample data were weighted to match the population of students and staff and were analysed using SPSS. Findings: The lifetime prevalence of prescription drug misuse (using prescription drugs not prescribed to the person) was 33% among students and 24% among staff. The main medications misused were pain relievers, followed by sedatives and sleeping aids. The main motives for misusing prescription drugs were to gain therapeutic benefit and "to get high". Conclusions: The study shows that a notable proportion of staff and students at the university used prescription drugs in a way that was not intended. The discussion draws attention to a debate about whether all forms of non-medical drug use should be regarded as misuse. The implications of non-medical use include health risks to the user as well as hidden social and economic costs. More research should be done to generate a more in-depth understanding of prescription drug misuse. (Contains 4 tables.)