Focusing upon a period during which the planning discipline emerged and was consolidated in Latin America from the 1920s through the 1950s, this article aims to identify some of the impulses behind the widening of the scope of planning activities undertaken by planners of capital cities, from the local and urban to the regional and territorial. The author uses a comparative perspective to analyze this tendency toward the enlargement of the territorial extent of the plan, interpreting it as part of the process through which Latin America's urban modernization proceeded while also relating it to the epistemological and professional shift from urbanismo towards planificacion and planejamento. While factors such as the emergence of planning offices in some capital cities and the emergence of the first courses in planning in university curricula are considered, the article focuses mainly on the the approaches of pioneers in Latin American planning to this transition, in particular Carlos Contreras and Hannes Meyer in Mexico City, Carlos della Paolera in Buenos Aires, Karl Brunner in Bogota and Santiago de Chile, and Maurice Rotival in Caracas.