The GREENHOOD project pioneers a comprehensive approach to address the global challenge of unbalanced nutrient flows in regional ecosystems. Operating across four European countries and one associated region, GREENHOOD focuses on re-balancing nutrient flows and reducing N/P emissions through five key strategies: a) Participatory Approach: Engaging diverse stakeholders through capacity building, governance labs, and cross-regional exchange activities to ensure inclusive decision-making. b) Estimation of Maximum Allowable Nutrient Inputs: Utilizing optimized budgeting methodologies, including novel modeling tools and socio-economic data, to assess the impacts of new balancing practices. c) Demonstration of Effective Nutrient Management Strategies: Leveraging insights from previous R&D experiences to develop and demonstrate solutions for nutrient excess prevention, reduction, and recycling in key sectors such as agriculture, wastewater treatment, aquaculture, and forestry. d) Establishment of Regional Nutrient Circular Economy Schemes: Creating schemes to close nutrient flow gaps between sectors like livestock-agriculture and aquaculture-agriculture, evaluating the agronomic performance and market uptake of bio-based fertilizers and by-products. e) Innovative Governance Measures: Showcasing governance measures to incentivize the adoption of nutrient-balancing solutions, collaborating with regional administrators and supporting existing policies. GREENHOOD also emphasizes effective dissemination and exploitation of results by collaborating with strategic initiatives like CCRI and Mission projects, as well as conducting regional twinning programs. Through these efforts, GREENHOOD aims to pave the way for societies to operate within safe ecological boundaries while meeting socioeconomic needs.