Local air pollution, and the health problems it causes, have received increased attention in many parts of the world, often because of specific incidents in major cities. However, over the last few years, the evidence-base has improved significantly, and now demonstrates that the health impacts of local air pollution, particularly from road transport, are much larger than previously thought. Drawing on this improved evidence-base this study estimates the economic cost of the health impacts of air pollution from road transport – on a global scale, but with special reference to People’s Republic of China, India and the OECD member countries.