Background : Air pollution contributes to mortality and morbidity. We estimated the impact of outdoor (total) and traffic-related air pollution on public health in Austria, France, and Switzerland. Attributable cases of morbidity and mortality were estimated. Methods : Epidemiology-based exposure-response functions for a 10 ug/m3 increase in particulate matter (PM10) were used to quantify the effects of air pollution. Cases attributable to air pollution were estimated for mortality (adults >=30 years), respiratory and cardiovascular hospital admissions (all ages), incidence of chronic bronchitis (adults >=25 years), bronchitis episodes in children (<15 years), restricted activity days (adults >=20 years), and asthma attacks in adults and children. Population exposure (PM10) was modelled for each km2. The traffic-related fraction was estimated based on PM10 emission inventories. Findings Air pollution caused 6% of total mortality or more than 40 000 attributable cases per year. About half of all mortality caused by air pollution was attributed to motorised traffic, accounting also for: more than 25 000 new cases of chronic bronchitis (adults); more than 290 000 episodes of bronchitis (children); more than 0·5 million asthma attacks; and more than 16 million persondays of restricted activities. Interpretation This assessment estimates the public-health impacts of current patterns of air pollution. Although individual health risks of air pollution are relatively small, the public-health consequences are considerable. Traffic related air pollution remains a key target for public-health action in Europe. Our results, which have also been used for economic valuation, should guide decisions on the assessment of environmental health-policy options.