Abstract Technological improvements of HVAC-systems, buildings and other energy consuming products can support a reduction of CO2 emissions. The implementation of energy efficient technology is important to reach the climatic goals of the Paris agreement. As cities are the main contributors of greenhouse gas emissions, they offer great potential for implementation of energy efficiency measures and emission reduction. Thus, the question arises on how to support the implementation process. The main challenge is not only the implementation and usage of technologies, but also the optimisation of existing local instruments, processes and frameworks to efficiently support the implementation of energy strategies in communities. This paper summarises results of the Annex 63 − Implementation of Energy Strategies in Communities − within the Energy in Buildings and Communities Program (EBC) of the International Energy Agency (IEA). It includes procedures and best-practice examples to implement optimized energy strategies in communities. The implementation strategies deals with visions and targets, renewable energy strategies, legal frameworks, design of urban competition processes, tools supporting the decision making process, monitoring, stakeholder engagement, socio-economic criteria and organisation structures. For all of these strategic measures, specific guidelines were elaborated together with a worldwide network consisting of representatives from cities, urban and energy planners, consultants, universities and many other stakeholder groups.