An assessment of local and regional air-quality forecasts for London, UK is reported in the International Journal of Environment and Pollution. In their evaluation, Amy Stidworthy, Mark Jackson, Kate Johnson, David Carruthers, and Jenny Stocker, of Cambridge Environmental Research Consultants Ltd., explain how levels of nitrogen oxides, ozone, and sooty particulates (PM2.5 and PM10), can be predicted quite accurately but the origin and how the various pollutants are dispersed must be taken into account in forecasts to ensure accuracy.