My dissertation is a history of the Santiago metro system in the context of changing techno-political regimes in Chile. My central question is why public transportation became a shared concern among diverse actors between 1965 and 1990 and how their proposals changed over time. Planning for the metro began in 1965, during a period of democratic state-led development under President Eduardo Frei. Transnational from the start, the metro united Chilean engineering with French technology, funding, and expertise. Construction proceeded during the democratic socialist government of Salvador Allende. After the 1973 coup that ousted Allende, the military junta continued to support the project, as did the French funders and consultants. Both before and after the coup, metro planners made claims for the project's importance in terms of apolitical technical criteria. The first metro line opened in 1975, the year that the neoliberal "Chicago Boys" began to occupy influential positions in the new government. Amid a climate of economic austerity and boom and bust cycles, construction proceeded slowly throughout the 1970s and 1980s. My research ends in 1990, just after the metro was converted to a state-owned corporation, and as the dictatorship came to an end. Given this shifting political terrain, why did the metro remain a viable project? What social and political work did the technocratic discourse of metro planners accomplish? My research examines collaboration and conflict between Chilean and French professionals, state agencies and private businesses, technological experts and users, and planners and urban residents. Cutting across democratic and authoritarian periods, this project illuminates degrees of continuity and discontinuity in Chilean state formation. At the same time, it historicizes contemporary debates about the role of the state in providing transportation as a public good.