The use of simulation tools in the urban context, connected to 2D or 3D web-based visualization applications, are valuable tools for decision-makers and citizen’s engagement. If we talk about improving the sustainability of the building stock in vulnerable neighborhoods, innovative social and economic models need to be considered under an holistic perspective that accounts also for interactions with mobility, circularity and co-creation processes with public authorities and citizens. In this direction, the aim of the DUT Making PEDs project is not only to research and plan Climate Neutral Plus Energy Districts (PEDs), but also to facilitate the transition into practice providing Digital Twins as a means to support decision-making and participatory urban transformation processes. Specifically, the project focuses on: i) an holistic assessment towards Climate Neutral PEDs; ii) a reliable prediction of potential sustainability and business scenarios on large-scale energy retrofitting actions of the building stock; iii) the impact of Citizen Energy Communities (CECs). Developed digital twins and models will be tested and refined while supporting decision-making processes for the regeneration of four districts in Europe aiming to climate neutrality, acting as Urban Living Labs (ULLs), in the cities of Linz (Austria), Civitavecchia-Rome (Italy), El Prat (Spain) and Bærum (Norway).