The present study re-evaluates the Progressive era in the United States from the standpoint of capitalist reproduction, yet does so in a way that ultimately transcends Marxist economic determinism. It considers the ways in which ‘progressive’ discourses problematized urban issues in such a way that these shaped knowledges and subjectivities which were instrumental in the shaping of the American metropolis during the period between 1894 and 1950. The city, and its physical features, operated as an interface between actors and the abstract aggregation of their actions in what would eventually be conceptualized as “the economy”. This study considers how the built environment, which served as such an interface, also was problematized as a site for economic, social and political intervention. This urban discourse in which these problematizations occurred is the protagonist of the thesis, since it is within that discourse that knowledge and subjectivity seem to have formed.