The differences between female and male general practitioners (GPs) were studied regarding three different factors: 1) Do female GPs see more female patients than their male colleagues in the same practice?; 2) Are female GPs confronted with different types of health problems from their male colleagues?; and 3) Do female GPs provide different services to their patients? Data from the Dutch National Study on Morbidity and Interventions in General Practice were used. All practices in this study with both female (n = 23) and male (n = 27) GPs were selected. This resulted in detailed data on 47,254 consultations, 62% of which were with female patients. The three research questions all received an affirmative response: 1) female patients tend to choose female general practitioners; 2) female GPs see different health problems from their male colleagues, and that is only partly because the patient so chooses; and 3) besides the expected differences in female-specific problems, there is a clear GP-gender effect in the presence of 'social' and 'metabolic' problems in the female GP's consultations. Some differences in the provision of services between male and female GPs occurred, with female GPs spending more time on their patients and having a stronger tendency to provide continuity of care. In addition to a gender effect (both physician and patient) a part-time effect in most issues studied was observed.