This research focusses on the decision-making processes of energy regions regarding the energy transition in The Netherlands. The Netherlands has ratified the Climate Agreement in 2019, which thirty energy regions combined need to put in their efforts to reach the target of producing 35 TWh in 2030. One of the key elements in the energy regions is the active involvement of citizens through participation. However, a good relationship between the municipalities in the energy region is not self-evident. The thirty energy regions in the Netherlands have the task to form and lead and provide access to information and other forms of citizen support. Every energy region takes its own approach to involve citizens in their energy transition decision-making. Therefore, it is interesting to study to what extent and in which manners energy regions are able to involve citizens in the RES decision-making and in which ways governments are able to live up to their own participation goals. This embedded case study focusses on energy region Holland Rijnland, with a focus on six municipalities in this region: Katwijk, Leiden, Lisse, Zoeterwoude, Alphen aan den Rijn and Nieuwkoop. Taken the challenges and research objectives from previous paragraphs into consideration, the following main research question can be formed: “In which ways is citizen participation present, organized and influencing the initiation, design and implementation phases of the energy transition in the energy region Holland Rijnland?”