If we take the rhetoric of recent academic and policy discourse at face value, crossing disciplinary and institutional boundaries and engaging extra-scientific actors in the production and distribution of knowledge has become a kind of ‘gold standard’ . This is particularly true for fields like sustainability research, which is supposed to address the complexity of so-called ‘grand challenges’ of contemporary societies. Investigating the projects of a funding scheme for participatory sustainability research, this paper explores how researchers frame participatory research practices in their prospective narrations in research proposals and in their retrospective reflections in the framework of interviews. Thereby we focus on their stories about (1 ) the overall value of participation, (2) the roles allocated to different actors, (3) the temporal organization of participation as well as the (4) spatial dimension of collaboration. Building on this analysis, the paper concludes that even though participatory research programs create new possibilities, they remain limited in scope as they operate in an environment in which this kind of cross-boundary work does not fit the established standards. This strongly limits any form of “collective experimentation” and new ways of learning in sustainability research and beyond.