To assess knowledge of capacity issues across different medical specialties we conducted a cross-sectional survey with a structured questionnaire at academic meetings, lectures and conferences. Of 190 individuals who received the questionnaire 129 (68%) responded-35 general practitioners, 31 psychiatrists, 29 old-age physicians [corrected] and 34 final year medical students. Correct answers on capacity to consent to or refuse medical treatment were given by 58% of the psychiatrists, 34% of the geriatricians, 20% of the general practitioners and 15% of the students. 15% of all respondents wrongly believed that a competent adult could lawfully be treated against his or her will, with no obvious differences by specialty. As judged by this survey, issues of capacity and consent deserve more attention in both undergraduate and postgraduate medical education.