This dissertation examines how housing policy and urban planning became tools for governance, sanitary reform, and economic restructuring in Northeast Brazil from the late nineteenth to the twentieth century. Instead of evaluating these policies’ direct impact on workers, this study foregrounds the symbolic power of public housing as a political and ideological project. Policymakers consistently framed mass housing as a means to instill hygienic practices, assert social control, and manage economic transformations. Across varying political regimes—from early sanitarians targeting mocambos (informal settlements) in Pernambuco and Rio Grande do Norte to developmental planners influenced by international discourses—housing remained a critical instrument of governance. Drawing from archival sources such as policy documents, correspondence, newspapers, and reports, this dissertation explores how politicians, sanitarians, urban planners, and social workers conceptualized housing programs. In the turn of the nineteenth to the twentieth century, reformers in Pernambuco and Rio Grande do Norte sought to eradicate mocambos (informal settlements), presenting them as obstacles to hygiene and economic development. During the Vargas era, the expansion of state-led housing through pension funds and regulatory institutions institutionalized housing as a governmental concern. By the mid-century, Brazilian authorities incorporated global development ideologies from organizations such as the United Nations and the Alliance for Progress, aligning national housing policies with international discourses on modernization and developmentalism. In the 1970s and 1980s, housing shifted toward financialized markets, prompting grassroots resistance demanding equitable urban infrastructure. This dissertation reveals authorities' persistent obsession with housing as a tool for governance across political and ideological shifts, unveiling broader transformations within the federal government itself and national and transnational networks of funding, experts and expertise. By placing Northeast Brazil within global debates on housing and urbanization, this research contributes to Latin American urban history, labor studies, and histories of technology and development, demonstrating housing’s centrality not merely as infrastructure but as a contested reflection of state ideologies and modernity.