The paper reviews the available literature with regard to human health effects of fine particulate matter (PM10, PM2.5) from a Danish perspective. Fine particulate matter is not routinely measured in any Danish air pollution monitoring programme. Preliminary surveys show elevated PM2.5 levels in Copenhagen corresponding to levels found in other cities in Europe and the USA, and a close relationship between outdoor and indoor concentrations. It has been roughly estimated that about 400 people in the Greater Copenhagen area may suffer a premature death due to airborne fine particulate matter. A limited number of Danish studies support the view that health effects (respiratory symptoms and increased medication) can be observed in sensitive city populations at air pollution levels well below international air quality standards.