Making territorial R&I governance more open and inclusive by engaging citizens and multiple stakeholders in the definition and implementation of regional policymaking. This is the purpose of TRANSFORM - Territories as Responsive and Accountable Networks of S3 Through New Forms of Open and Responsible Decision-Making - a Coordination and Support Action funded by the European Commission under the Horizon 2020 Programme. To achieve its goal, TRANSFORM brought together three European regions, Lombardy (Italy), Catalonia (Spain), and Brussels-Capital (Belgium), to design and test three sound methodologies: participatory research agenda setting, citizen science, and multi-stakeholder engagement practices. TRANSFORM builds on Responsible Research and Innovation (RRI), a concept promoted by the European Commission to better align research and innovation with societal views, needs, and expectations. It provides regional public authorities and other interested R&I actors with inspiring examples and practical suggestions, emerging from real regional settings and experimentations, on how to put these principles into practice. The three regions involved in TRANSFORM implemented a mutual learning process, also pairing with CC-PES initiative in Boston (Massachusetts, US), a project aimed at opening the public dialogue on science and innovation. At the end of its 3-year journey, TRANSFORM collected the most relevant reports, articles, and multimedia products in this e-book as an as easy-to-use guide for all interested actors.