Who are boundary spanners and how can we support them in making knowledge more actionable in sustainability fields?

Meeting today's environmental challenges increasingly requires individuals who are able to operate at the boundary between science and policy. This work can involve mediating, bridging, and brokering knowledge. In practice, a range of challenges limit both the capacity and number of individuals who are able to serve, and serve effectively, in these roles. We draw on recent literature to synthesize these challenges and characterize ‘who' boundary spanners are and what they do. Through the articulation of their unique attributes and functions, we explore opportunities for cultivating and legitimizing the role of boundary spanners, along with formalization and recognition of the profession. We reflect upon our own professional experience as boundary spanners to bring deeper meaning and understanding of how to build greater support while capturing key challenges in the field. We argue that greater acknowledgement and professionalization of boundary spanning will improve the use of science in practice and knowledge to action.