All simple relationships are like one another, but each complicated relationship is complicated in its own way. In the early 1930s, just when the DSP-IHD collaboration had settled into a comfortable pattern of give and take, Mexico began an intense period of political activism. With the waning of most regional conflict, the various parties to the Mexican Revolution vigorously reiterated their claims on the state. Peasants and industrial workers, in particular, demanded their rights, as embodied in the 1917 Constitution. Lázaro Cárdenas's election to the presidency in 1934 did not signify an end to the turbulence, instead launching an era of social rumblings, redistributive justice, and heightened nationalism—all within the context of a growing central government and continued capitalist development.

In this atmosphere, virtually every element of society—from labor to the arts, industry, and government—was undergoing a frenzy of institutionalization and bureaucratization. Now that Mexico was able to channel its full energies to the building and rebuilding of the nation, the three pillars of revolutionary politics from the 1920s—education, public health, and nationalization of resources— needed to quicken their move from rhetoric to policy. In the health arena, significant expansion occurred in multiple areas, with special attention to local health services, public health research, industrial hygiene, and professional training and placement. This period of activism also framed the emergence of rural health policies that were creatively suited to Mexico's modernizing—yet still heavily agricultural— economy: growing ranks of progressive public health and medical professionals joined forces with the revived system of traditional collective farming in the provision of much-needed health care for the rural population.

How might the RF's interests fit into this agenda? At first, it was not clear if the IHD-DSP partnership would survive Mexico's political and social mobilization; the RF seemed to be pulling away despite the DSP's relentless pursuit of its cooperation. As the DSP gained momentum in implementing its own mix of social medicine and popular health, the IHD redirected its attention to the training of Mexican health professionals in both Mexico and North America.

While the IHD-DSP collaboration was facing a period of uncertainty, binational relations were on firmer ground. The United States’ “Good Neighbor” policy, under President Franklin D. Roosevelt, inaugurated an era of improved U.S. behavior toward Latin America.