To determine general practitioners' attitudes to national health insurance (NHI) and to capitation as a mechanism of reimbursement. To explore determinants of these attitudes.Cross-sectional survey by means of telephone interviews; four focus group discussions.Cape Peninsula.174 GPs randomly sampled from a total population of 874.Acceptance of NHI, acceptance of capitation.63.3% approved of NHI. More than 81% approved of NHI if GPs would be able to maintain their independent status, e.g. own premises and working hours; 82.3% said NHI would be a more equitable system of health care, 88% approved of the fact that NHI would make care by GPs more accessible, and 73% said they would have the capacity to treat more patients. However, 61.3% of GPs disapproved of capitation as a form of reimbursement.Most GPs in the Cape Peninsula were amenable to some form of NHI. However, the proportion of GPs who approved the introduction of NHI varied depending on details of the NHI system such as payment mechanisms, workload, income and effects on professional autonomy. A national survey of medical practitioners is recommended. The implications of GPs' preferences concerning the reimbursement mechanism for the feasibility of implementing a NHI system in South Africa require serious consideration by policy-makers.