This dissertation explores the role of low-income housing in the development of two major Latin American societies that underwent demographic explosion, rural-to-urban migration, and growing urban poverty in the postwar era. The central argument treats popular housing as a constitutive element of urban development, interamerican relations, and citizenship, interrogating the historical processes through which the modern Latin American city became a built environment of contrasts. I argue that local and national governments, social scientists, and technical elites of the postwar Americas sought to modernize Latin American societies by deepening the mechanisms for capitalist accumulation and by creating built environments designed to generate modern sociabilities and behaviors. Elite discourse and policy understood the urban home to be owner-occupied and built with a rationalized domestic layout. The modern home for the poor would rely upon a functioning local government capable of guaranteeing a reliable supply of electricity and clean water, as well as sewage and trash removal. Rational transportation planning would allow the city resident access between the home and workplaces, schools, medical centers, and police posts.

As interamerican Cold War relations intensified in response to the Cuban Revolution, policymakers, urban scholars, planners, defined in transnational encounters an acute "housing problem," a term that condensed the myriad aspects involved in urban dwellings for low-income populations. The policy outcome of these encounters was the arrival of foreign economic and technical assistance dedicated to slum eradication and publically-financed popular housing. Within the policy and social sciences circuits of modernization theory during the Cold War context, housing policy emerged as a discursive and practical antidote to the problem of sheltering a burgeoning urban population and its attendant attributes of underdevelopment, poverty, and social unrest.

The dissertation demonstrates how a handful of selected cases of popular housing erected in Rio and Buenos Aires ultimately did not fulfill the stated goals embraced by the proponents of developmentalism and interamerican assistance. It shows the extent to which a shortfall of outcomes relative to goals was indicative in part of hemispheric transitions, but also of the particularities of the modernizing city in the second half of the twentieth century.