The three main methods of paying individual health care workers – salary, fee-for-service and capitation, influence health provider behaviour in different ways. However, this behaviour is not well understood and there is evidence that a wide range of factors including financial incentives, training, regulation, professional and ethical norms, influence their clinical decisions. Research in South Africa aims to investigate these dynamics in more detail, and considers their relevance to the design of reimbursement mechanisms and the implementation of national health insurance.