With an overall aim to support the coherent implementation of the EU (European Union) Biodiversity Strategy (EUBS) 2030, the Convention on Biological Diversity (CBD) post-2020 framework, as well as the EU Green Deal, MSP4BIO develops and demonstrates the ways in which knowledge-based MSP becomes a vehicle and a tool for the protection and recovery of ecosystems. Specifically, MSP4BIO will develop an integrated flexible socio-ecological management to cope with a rapidly changing environment for coastal, offshore, and deep-sea ecosystems and validate its concrete applicability in 6 test sites in 5 European Sea Basins. The management relies on improved systemic biodiversity prioritization criteria for MPAs and EBSAs, based on the best available scientific knowledge on biodiversity attributes, and linking spatial ecological features (including migratory ones) with socio-economic considerations. MSP4BIO uses a participatory approach to co-develop ecosystem services trade-off scenarios to prioritize the areas and assess the suitability of spatial and strategic management measures from the ecological and socio-economic perspectives. The approach integrates the criteria and objectives of relevant maritime and biodiversity policies as well as the EUBS 2030 to ensure coherent policy implementation. As such, the project will develop and improve approaches, methods, and tools to feed scientific knowledge, making it of direct use to planners and MPA managers, while producing site-specific results informing site-specific, and broader policy processes and decisions. The project builds on and integrate existing knowledge and results from multiple origins, and ensures effective collaboration with relevant projects and initiatives to fill present gaps on marine biodiversity, speeding up the scientific brake while paving pave the way for effective biodiversity management.