Small- and medium-sized communities might prove to be game-changers in the overall energy transition because many problems have to be solved within their ambit. Urban planning is dealing with the numerous processes of urban change. Energy is a fairly new task to be addressed and many stakeholders lack experience and criteria for strategic decision making. The overarching research question of this thesis is: What do decision makers in small- and medium-sized communities need to become more successful in implementing energy transition processes? For the research project this general question was broken down into four primary research questions: • How can communities anchor and monitor long-term energy transition visions in their communal development plans? • What tools and models are available for urban energy system analysis? • How can tools and models be adapted to the specific demands and boundary conditions in the case study communities to ensure long-term implementation of appropriate technologies and measures? • How does the practical implementation of the adapted tools work in the case study and what barriers must be overcome for long-term success? To answer these questions a combination of review of the current state of scientific literature of the thematic field with a practical application and evaluation of ‘real’ implementation projects was chosen.