Participatory and responsive approaches to research strive to be democratic, inclusive and impactful. Participatory researchers share a commitment to epistemic justice and actively engage citizens and users as well as other stakeholders in the co-creation of knowledge for social change. While more and more researchers and policymakers feel attracted to these approaches in practice, the normative ideals of social inclusion and justice are sometimes hard to realize, because of established interests, power relations and system requirements. In this article I argue that participatory researchers and evaluators have a moral responsibility to do ‘ethics work’. This is more than just following ethical principles and codes of conduct. ‘Ethics work’ entails the labour and effort one puts into recognizing ethically salient aspects of situations, developing oneself as a reflexive practitioner, paying attention to emotions and relationships, collaboratively working out the right course of action and reflecting in the company of critical friends. In this article I present the theory and ethics of participatory approaches, illustrate ethical issues and ethics work related to collaboration, politics and power, and share lessons based on ten years of practice in the field of health and social well-being.