The project ‘Institutionalized Integrated Sustainable Energy and Climate Action Plans’ (2ISECAP) aims to bridge the gap between local sustainable energy planning and implementation by supporting the capacity building of public authorities and by developing interface capacities within public authorities to engage with civil society towards energy transition. 2ISECAP will attempt the creation of an institutional environment for effective decision-making processes combining the democratic legitimacy and legal power of formal plans/policies with the creativity, energy and social capacity of bottom-up initiatives, entrepreneurship and community involvement. 2ISECAP will develop and apply an innovative holistic approach for participatory and integrated sustainable energy and climate actions planning that considers the required institutional tools, legal frameworks and local initiatives. Emphasis will be given on driving the sustainable energy transition at cities level through the Climate City Contracts. The planning approach will enhance SECAPs visibility and implementation capacity and the development of sustainable relationships between government and civil society. 2ISECAP utilizes the Living Lab (LL) concept to activate participants to co-create knowledge, energy plans and future policies. The project will provide experiential learning to 6 European Municipalities, by applying 2ISECAP approach to revise/develop their SECAPs, within a LL environment. Eight EU Countries are involved in 2ISECAP. Over 100 public officers will enhance their institutional and technical capacity on participatory integrated planning and governance structures engaging civil society on local energy transition. At least 6 institutionalized collaborations between public authorities are expected to derive and about 30 policies to be influenced. In total, more than 1,300 stakeholders will be informed on Integrated SECAP planning and 5,500 citizens will be involved in the project’s activities.