Objective: To assess the prevalence, nature and outcome of medical emergencies experienced by general dental practitioners (GDPs) over a 10-year period. Design: Postal questionnaire survey of a random sample of GDPs in Great Britain. Subjects: 1500 GDPs, 1000 in England & Wales and 500 in Scotland. Results: There was a 74% response. Emergency events were reported by 70.2%: the number reported by a single individual ranged from none to 33. The most commonly experienced events, including those associated with general anaesthesia, were (as a percentage of the total) for England & Wales and Scotland, respectively: fits and seizures (31.0%, 36.3%); swallowed foreign bodies (15.7%, 18.1%); attacks of asthma (13.8%, 11.1%); chest pain associated with angina pectoris (10.1%, 11.0%) and diabetic events (10.6%, 9.0%): none of these resulted in any serious sequelae. More events were reported in Scotland. Overall, there were 20 deaths resulting from medical emergencies reported in the survey, 4 affecting passers-by and none associated with general anaesthesia. 8849 years of practice experience were represented (by 94% of respondents), from which an estimate of the frequency of events was made. Conclusions: An emergency event was reported, on average, for every 4.5 practice years in England & Wales and 3.6 years in Scotland and death associated with general dental practice, on average, once in 758 and 464 years, respectively. © British Dental Journal 1999.