Complementary, or alternative, medicine has increased in popularity among patients during the past 20 years. The purpose of this study was to determine whether general practitioners met their patients' expectations with regard to complementary medicine. In a postal survey all 71 accredited general practitioners in the district of Kassel, Germany, received a structured questionnaire about their experience with complementary medicine. Forty (56%) replied. In 10 of these practices 310 patients were interviewed about their attitudes towards and expectations of such treatment. Of the responding doctors 95% used, at least occasionally, some form of complementary medicine (most commonly herbal medicine, neural therapy or homeopathy). All but three patients accepted the value of complementary medicine, 58% of them (especially younger, more highly educated patients and those from rural practices) preferred it to orthodox medicine and 40% of the patients had received some form of complementary therapy. Nearly 70% of the patients requested that complementary medicine be practised by their general practitioner more frequently than at present. There was no significant link between patient satisfaction with the doctor and patients' view of, or demand for, complementary medicine. Although both patients and practitioners were interested in complementary therapy, there was a gap between the willingness, or the ability, of general practitioners to use complementary medicine and the patients' demand for these alternative forms of treatment.