In light of the challenges imposed by climate change, many countries are 'planning’ for energy transition. Interactions between different actors in transition arenas, help shift the current complex socio-technological energy system towards a new sustainable one. A critical issue is integrating the new energy system with other land-uses and spatial issues. In the Netherlands, regional design ateliers were organized to explore and address these challenges. We conceptualized the regional design ateliers on energy and space as systemic transition arenas in planning for energy transition and analysed their contribution to the regional energy transition process. The design ateliers played an important role in creating insights into regional energy transition and its spatial implications. This raised awareness and affected the perspectives of several stakeholders on energy transition. Our study also showed that some important (spatial) aspects, such as smart combinations with other land-uses and the transport and storage of energy, received little attention during the ateliers, leading to unfinished conversations. We argue that regional design ateliers should also be organized in the upcoming stages of ‘planning’ for energy transition to further fuel the transition process and fully exploit the benefits of regional design ateliers as systemic transition arenas.