This paper reviews regulation of medical work based on concepts available in the specialized literature. It proposes the model developed by Moran and Wood to analyze the regulatory process in the Latin American context. However, any conceptual model used for the analysis of regulation should consider the changes generated by the reform in the interaction between financial and regulatory agents and health care providers. The regulatory function is involving an increasing number of groups interested in the appropriate performance of health services. Regulation of medical work is a dynamic issue requiring close analysis.