This article aims to contribute to the debate on the SUS regionalization policy and the establishment of health regions in Brazil. Understanding them require to recognize the dichotomy between public health and individual health - which marks the history of Brazilian public health - and identify the different rationalities that lead this process. Such rationalities allow not only to consider the legacy of municipalization in the current regionalization process, as well as to establish links between the two fields of fundamental knowledge to the debate, epidemiology and geography. Clinical epidemiology, privileging individual health, gives basis to a healthcare model that prioritizes the optimization of resources. The recognition of health in its broader concept, in the social epidemiology, bases an attention model aimed at social determinants. With geography, functional regions can be formulated, based on Christaller's theory, or lablachianas regions which recognize the social loco / regional structure, allowing intervention in determining or conditioning the way of illness and death of populations.
Regionalization in Health; Health Regions; Municipalization in Health; Brazilian National Health System