This paper discusses the approach, challenges and outcomes of delivering a water-sensitive urban design, incorporating comprehensive sustainable drainage systems (SuDS), for a major eco-town in Oxfordshire, UK. The 406 ha North West Bicester development is the UK's first eco-town, involving 6000 new homes and associated social, commercial and environmental infrastructure. A key challenge was to deliver the government's ambitious criteria for eco-towns while working in a large multi-disciplinary setting with the public and other stakeholders. The key aims of the project are to respond to climate change, create enjoyable and liveable cities, promote healthy lifestyles, design multi-functional and interconnected green infrastructure, reduce flood risk and maximise multiple benefits. Common barriers to the uptake of SuDS include limited evidence in quantification of economic benefits along with maintenance concerns. This paper demonstrates that the initial 17·5 ha of the exemplar site, comprising 393 homes, will deliver natural capital benefits of £307 550 per year from the proposed SuDS, thus highlighting economic benefits and easing maintenance concerns.