We describe a survey of general practitioners in the Northern Region which was carried out during the summer of 1977 as the result of a commission from the Education Committee of the North of England Faculty of the Royal College of General Practitioners. Seventy-five per cent of a one in two random sample of general practitioner principals returned a postal questionnaire in which their perceptions of postgraduate education were sought and their behaviour measured by the number of sessions they attended during the previous year at their 'usual' and other postgraduate centres. Almost half the respondents had more than a basic qualification and all but three per cent had held full-time hospital appointments, two thirds of them at the level of senior house officer or above. Their experience as general practitioner principals averaged 15 years and 57 per cent held part-time appointments outside their practices. Only four per cent had not attended any postgraduate events during the previous year but the remaining respondents had attended eight sessions on average, six of which were at their usual centres. Those attending more than the average number of sessions tended to have registered between 1950 and 1969, to work in larger practices, to hold additional appointments, or to be trainers or College tutors. Most of the respondents were conservative in their perceptions of teaching methods, the topics discussed at meetings, and the contributors to postgraduate education but the younger general practitioners and a group of established general practitioners affiliated to the Royal College of General Practitioners held more radical views. They agreed about the primacy of traditional clinical topics but were sceptical of the value of ward rounds and formal lectures and favoured the seminar and clinical attachments. They saw a need for more material about practice management and wanted experienced general practitioners and community paramedical staff as teachers in addition to hospital consultants. Most of the respondents believed that their usual centres were well organized and managed but failed to cater for the special requirements of general practitioners in non-clinical aspects of practice. Lunchtime and evenings were seen as the most convenient for weekday meetings and Sunday as the most convenient day of the week. A majority of respondents believed that post-graduate education had altered their practice of clinical medicine but only 15 per cent believed it had caused changes in their practice organization.