Smart energy transition exports at the municipal level are gaining importance and go far beyond implementing single projects. Decarbonising cities involves complex strategic planning and needs system level thinking and changes. This has been increasingly realised at the municipal level, but challenges remain regarding the tools, involvement of stakeholders and on the development of policies. The focus of the research is on the use of participatory foresight for fostering smart energy transition on a municipal level, the key benefits and success factors that participatory foresight brings, and the replicability of this approach. Within the novel Cities4ZERO framework, an overarching methodology for a smart urban decarbonisation transition, guiding cities through the process of developing the most appropriate strategies, plans, projects, as well as looking for the commitment of key local stakeholders for an efective transition–foresight framework, was developed and tested in five pilot cities. Foresight as applied within the Cities4ZERO framework creates a participatory process which brings stakeholders together to achieve unified scenarios, and a common vision for future urban decarbonisation strategies. The methodology is replicable and increases the quality of strategic energy planning by fostering long-term system thinking.