The author, a specialist in community-based approaches and health inequalities, examines three key questions raised by participatory practices in health: who participates and what is the legitimacy of their representation; what processes are at work in participatory spaces; and what tools facilitate these processes. She highlights the lack of theoretical studies of these processes, the limited use of the body of work in the sociology of action, and the absence of theoretically grounded tools that decision-makers interested in participatory approaches could utilize. She advocates for a serious and critical examination of the participatory initiatives implemented by the healthcare system.