[Brief organizational history of epidemiological surveillance at the IMSS].

The Mexican Institute for Social Security (IMSS) has been an institution that has been forged over 80 years of existence, with contributions to the history of public health and epidemiological surveillance in Mexico; to do so, over the course of its institutional life, it has had to adapt to the contexts, realities, challenges and unforeseen events in terms of medical, sanitary and epidemiological care. In this sense, the Institute has modified its organizational structure on several occasions at managerial level, and, consequently, within the federal entities and in the medical care units. For this reason, this manuscript summarizes the main milestones and events that the Institute has experienced, focusing on its organic structure related to epidemiological surveillance; for example, the birth of the Epidemiological Surveillance and Contingency Support Coordination, as well as the Network of Laboratories for Epidemiological Surveillance and its growth, following a review mainly of the organization manuals of the Medical Benefits Administration and various institutional reports that are published annually, with many successes that have resulted from these changes and the alliances within the Institute, as well as the external ones that recall the strength and flexibility of the Institute's organizational structure.