“That was not the discussion we wanted ...

Responsible Research and Innovation calls for comprehensive public and stakeholder involvement. Its specific requirements, however, have raised criticism concerning the limitation of engagement opportunities for actors like Civil Society Organizations that do not share mainstream perspectives on technological innovations. Our article investigates the engagement of critical Civil Society Organizations in public debates and dialogues on synthetic biology and asks how they contribute to opening up respective debates. Based on three case studies, we show how Civil Society Organizations engage in and frame the debate on synthetic biology in different organizational formats. We find that Civil Society Organizations have explicitly challenged visions of a sustainable future by airing concerns about its risks and adverse impacts and engage in ontological debates about synthetic biology. Yet, we argue that different engagement formats are needed to ensure a diverse public debate on synthetic biology.