Following the introduction of the UK General Medical Council's regulations on the handling of poor medical performance, an interview and survey study was carried out among senior health professionals in the National Health Service (NHS). The aims of the study were to explore the respondents' perceptions of poor medical performance and to seek their experience of handling poorly performing doctors. Sixteen interviews were held face to face, followed by 28 telephone interviews. Subsequently, using similar questions to those in the interview schedule, a survey was carried out among senior health professionals across the NHS. Interview results identified a number of barriers to resolving poor performance, such as the unwillingness of some doctors to seek advice and the protective culture which prevented complaints being made against doctors. Survey respondents had high standards by which they judged poor performance, but they were more hesitant about considering poor consultation skills as being of the same significance as poor technical skills. However, problems with communication skills were the most frequently reported type of poor performance. The new arrangements for handling NHS doctors whose performance is perceived to be poor have much to do to overcome the barriers to effective action expressed by the respondents in this study.