This article is a contribution to methodological discussions on the “participation” pillar that guides strategies for Health Promotion. It reflects the conceptual and methodological bases of the Extended Communities for Action-Research (ECAR) as a tool for the Emancipatory Promotion of Health (EPH), taking as reference the experiences from the Territorial Laboratory in Manguinhos. The ECAR brings together researchers and mainly residents who live in the territory with their knowledge and distinct viewpoints who reflect on socioenvironmental problems, public policies and alternatives in a given context. Three key aspects for EPHare discussed: social participation, social determination and shared production of knowledge. Based on the experiences of the action-research model in areas with slums, we found a massive gap between what is written in the Policy and institutional practices where there were spaces marked by borders. We also noted a lack of rights and major tensions between the parties. As a result of the ECAR findings, various tools were produced in accessible languages facilitating knowledge appropriation and the enhancement of actions in social movements. This article concludes with some thoughts and challenges for the Emancipatory Promotion of Health.