The WeForming project aims to change the paradigm of efficiently managing energy in buildings, paying special attention to their interaction with the energy ecosystem (energy networks and markets) by developing, deploying and demonstrating innovative solutions addressing (i) digital operation, management and maintenance and (ii) efficient and interactive energy processing for Intelligent Grid-interactive Efficient Buildings (iGEBs), able to operate intelligently in a multi-energy, multi-user, multi-sector, multi-market, and multi-objective environment, without forgetting quality, comfort, health and acceptation. The WeForming Framework will deploy an umbrella framework covering all aspects around the establishment and adoption of iGEBs in cities, which consists of (i) a Building Operational Pillar encompassing all assets of iGEBs, including the energy management systems and the different platforms, aiming towards the building operational optimization, the actors and the actual flexibility resources, generation and storage components; (ii) a novel Interoperability Assurance Pillar which leverages on, adapts, evolves, and specifically validates leading-edge interoperable architectures; (iii) a Business Pillar including all necessary processes to bring the proposed solutions to the market, through the design and validation of sustainable and competitive business models, ensuring the economic viability of the investments needed for the establishment of smart cities featuring new and refurbished iGEBs; (iv) a Smart-city enabling Pillar integrating iGEBs as modular units addressing all different non-technical barriers and limitations for the widespread deployment of the proposed solutions that will create a stock of active buildings acting as active utility nodes within cities.