The authors identify and analyze patterns of community organizing among Latin Americans in Toronto for the period from the 1970s to the 2000s as part of a broader analysis of Latin American immigrant politics. They draw on the concept of social fields to map Latin American community politics and to capture a wide range of relevant organizations, events, and strategic moments that feed into the constitution of more visible and formal organizations. Five distinct waves of Latin American migration to Toronto produce three types of community organizations: ethno-national, intersectional panethnic, and mainstream panethnic groupings. This migration pattern also leads to a layering process as established organizations evolve and new migrant groups with specific priorities and ways of organizing emerge. The authors present a case study of the development and agenda-setting process of the Centre for Spanish Speaking People, a mainstream, multiservice, panethnic organization. Agenda setting is defined as the process of defining the vision and mission of an organization or cluster of organizations. The case study captures how a mainstream panethnic organization mediates between diverse in-group agendas of Latin American immigrants and out-group, specifically, state-generated, agendas, and how this agenda-setting process changes over time in tune with shifts in the political opportunity structure. The authors propose, however, that agenda setting is a dialogic social process that involves more than navigating the existing political opportunity structure. Agenda setting involves in-group and out-group dialogues embedded within a complex organizational field. It is an instance of political learning. The analysis of these dialogues over time for a specific group and organization captures immigrant politics in practice.