The Complementary Plans is a new instrument designed to build partnerships with the Autonomous Regions in R&D&I actions that have common objectives based on interests reflected in the State and Autonomous Region's Smart Specialisation Strategy (RIS3). Eight areas of scientific-technical interest have been selected within the EECTI lines: (1) Biotechnology applied to health, (2) Marine Sciences, (3) Quantum Communication, (4) Energy and renewable hydrogen, (5) Agri-food, (6) Astrophysics and high energy physics, (7) Advanced materials and (8) Biodiversity. In order to build territorial synergies, the Complementary Plans envisage the participation of several Autonomous Regions in a programme, with the possibility of participating in several of them. In this way, unique capacities and infrastructures can be harnessed, together with the possible participation of companies. The programmes will have a duration of 2 or 3 years, with co-financing commitments and co-governance mechanisms, boosting territorial economic transformation. By 2023, more than 260 million euro have been transferred to the autonomous regions. Reference C17 I1 in the Spanish Recovery and Resilience PlanProject locations Spain Project websitehttps://www.ciencia.gob.es/...