This article explores the construction of publicly financed low-income housing complexes in Rio de Janeiro, Brazil, and Buenos Aires, Argentina, in the 1960s. These housing developments were possible thanks to the arrival of foreign economic and technical assistance from the Alliance for Progress. Urban scholars, politicians, diplomats and urbanists of the Americas sought to promote middle-class habits, mass consumption and moderate political behaviour, especially among the poor, by expanding access to homeownership and ‘decent’ living conditions for a burgeoning urban population. As a result, the history of low-income housing should be understood within broader transnational discourses and practices about the ‘modernization’ and ‘development’ of the urban poor.