This thesis evaluates textual, visual and material legacies of modern architecture and urbanism in Mexico City between 1938 and 1964. There is a growing literature on the architects, architecture and urban development of Mexico City in the twentieth century, but few that provide an analysis of these material legacies beyond their claim as historical evidence. My research attends in detail to writing, drawing and building through key moments in the work of the Mexican architect Mario Pani. I analyse an archive of material that moves from his co-founding of the journal Arquitectura/México in 1938, to the construction of the Centro Urbano Presidente Alemán, a modernist housing estate in Mexico City in 1949, to the work of his Taller de Urbanismo (Urban Studio) between 1946 and 1964. I argue for an understanding of architectural and urban writing, building and drawing as ways of producing the world, rather than describing or responding to it. I demonstrate that latent geographical biases in the architectural writing of Arquitectura/México contributed to Mexican debates about architecture and the nation. A visual analysis of urban plans and research from the Taller de Urbanismo foregrounds their role in defining the problem of housing in Mexico City towards the legitimation of a specific genre of public housing. By examining the inauguration of the Centro Urbano Presidente Alemán, I uncover the materiality of the building as generative for the Revolutionary Mexican state. Within the context of emerging scholarship that rearticulates colonial circulations of urban planning and architecture within a framework of multiple or alternative modernities, I emphasise an attention to the co-constitution of writing, drawing and building, and their role in assembling the urban.