Intermediaries and Intermediation in Sustainability Transitions

Intermediary actors are key catalysts in accelerating sustainability transitions. Since 2019, the academic literature on intermediaries and intermediation has expanded rapidly, leading to inconsistent usage, proliferating lists of activities, and questions about their impact on transition processes. These challenges risk making the concept fuzzy and less accessible while limiting its practical relevance. This chapter provides an accessible introduction to intermediaries in sustainability transitions, followed by a historical account of the concept’s development. It then presents empirical examples of intermediaries and their activities, highlighting a key gap: the lack of an explicit theory on why intermediaries exist in transition processes. To address this, we position intermediaries alongside other actors, such as system entanglers, orchestrators, and champions. This chapter concludes by outlining future research directions, emphasizing the need to move beyond individual intermediaries to ecologies of intermediation as transitions accelerate and interact.