In the UK, the National Health Service (NHS) is one of England's largest employers and a major purchaser of goods and services, with a correspondingly huge carbon footprint of 18 million tonnes of CO2 per year. It has set itself an ambitious target: to reduce carbon emissions by 26% by 2020, by 80% by 2050 and, in the shorter term, by 10% from 2007 levels by 2015.