Sociotechnical transitions are complex processes that imply far-reaching technological, institutional and cultural changes. Transition intermediaries have emerged as potentially powerful actors and entities to speed up transitions. As much previous literature on intermediaries in transitions has focused on emergence, in this special issue, we focus on intermediaries in the acceleration phase of transitions. The contributions address different domains, with specific focus on different parts of the energy production and consumption system. The contributions cover three themes: intermediary actors in the diffusion of new solutions, in policy change, and systemic intermediaries. We end by making three observations regarding intermediation in the acceleration of sustainability transitions: new types of stakeholders coming into transition processes requiring new forms of intermediation; contestation and tensions becoming stronger, creating new challenges for intermediaries, and; potential confusion within intermediary actors.

社会技术转型是复杂的过程，意味着深远的技术，体制和文化变革。过渡中间人已成为加速过渡的潜在强大参与者和实体。由于先前有关过渡中的中介的许多文献都集中在新兴方面，因此在本期特刊中，我们关注过渡加速阶段的中介。文稿涉及不同领域，特别侧重于能源生产和消费系统的不同部分。文稿涉及三个主题：新解决方案的传播中的中间角色，政策变更和系统性中间人。最后，我们就加速可持续发展过渡中的中介问题提出三点意见：新型的利益相关者进入过渡过程，需要新的中介形式；竞争和紧张局势加剧，给中介机构带来了新的挑战，并且；中间角色之间的潜在混乱。