[Local health systems: a transition of the organized social response]

This paper discusses the transition of the organized social response in health with emphasis on local health systems. After reviewing a few basic definitions (health system, local health system, health care system, institutional system of health services), the author discusses the health transition (transition of the concept health-disease, technological transition, epidemiological transition, demographic transition, health care system transition) and the importance attributed to local health systems in Mexico.