[First steps of medical administration at the IMSS].

The creation of an institution as large as the Instituto Mexicano del Seguro Social (IMSS) required a lot of planning to manage all the benefits provided to the population. Thus, it is necessary to have health personnel with knowledge and experience in health services administration. This manuscript is an acknowledgment to doctors Manuel Barquín Calderón, Antonio Ríos Vargas and Carlos Zamarripa Torres, pioneers and recognized protagonists in the planning and organization (administration) of the IMSS medical services between 1945 and 1955, who also had rational initiatives and constructive, doing their duty. On the other hand, the Institute exposed and projected that medical-administrative activities were a complex task, and that its practice required specialized knowledge that could not be left to chance, empiricism, good will, beliefs or nonobjective imagination.