The concept of participation is currently evoked by constituencies as varied as urban planners, local governments, universities and social movements. This coincides with a revival of participatory research methods in the social and cultural sciences. This article argues that the critical potential of participatory research methods should not be taken for granted in cognitive capitalism, where participation is as much an instrument for governmental regulation from above as it is a practice for democratic self-determination from below. First, the politics of participation from the emancipatory departures of the 1970s to today's revival are being discussed. Second, based on a long-term ethnographic study on the transnational Euromayday movement of the precarious, it is demonstrated how positioning the researcher using reflexive ethnography can support a critical research attitude through a process of reflexive hybridisation. In concluding, reflexive activist scholarship is outlined as a critical research attitude which encourages participatory knowledge production in a way that responds both to the field of activism and the field of academia.