Createlli was commissioned by the municipality of Koekelberg to implement the citizen participation process of the municipal climate action plan. The municipality takes its responsibility to draw up a supported climate action plan to reduce CO2 emissions in the municipality and achieve the climate goals for 2030 (and 2050). Koekelberg chooses to go through a transparent process together with citizens, organizations and associations in which: challenges are identified, climate actions are prioritized and detailed,and the portfolio of climate actions is proposed to the municipal council. Together, we worked out an action plan in which the many actors and citizens showed their willingness to actively participate in implementation, since the greatest potential to reduce CO2 emissions lies with them. We chose several meetings and workshops (bilingual) and supported communication. During the activities we paid attention to co-creation, community building, ownership, forming a climate council and a concrete action plan, on which the municipality, residents and associations can build further.