trans4num aims to accelerate the transformation of agricultural systems in Europe and China by advancing Nature-based Solutions (NBS) for sustainable nutrient management and resilient food systems. The project combines scientific, technical, and socio-economic perspectives to optimise nutrient flows, evaluate NBS performance on seven demonstration sites (four in Europe and three in China), and develop a dynamic decision-support tool for regional nutrient management. At the same time, it investigates behavioural, policy, and value-chain factors that influence the adoption of sustainable practices, helping to identify and overcome systemic lock-ins. Through integrated research, multi-actor engagement, and cross-continental knowledge exchange, trans4num seeks to promote climate-friendly, biodiversity-enhancing, and socially grounded farming approaches that support a wider socio-ecological transition in agriculture and contribute to global sustainability goals.