The overarching goal of this project was to assess the potential for UK grasslands to deliver multifunctional objectives of carbon (C) sequestration, nutrient retention, pollination and biodiversity conservation, in working farming environments. The main focus of the project was soil C sequestration, and specific objectives were to: (a) assess the C storage potential of grasslands and the sensitivity of this C to management and climate change; and (b) experimentally test the potential to manage grassland vegetation diversity to optimise soil C storage. An additional aim was to test how variation in vegetation diversity and composition in agricultural grassland influences the provision of other ecosystem services, including nitrogen (N) and phosphorus (P) retention in soil, and pollination services, thereby contributing the overall multifunctionality of grassland systems. Our ultimate goal was to develop an improved mechanistic basis for management of C storage alongside other ecosystem services in UK grassland, thereby providing policy relevant tools for managing soil C and offsetting C emissions, with potential benefits for other ecosystem services.