Recent convergent data suggest that air pollution affects the risk of acute atherothrombotic events including both myocardial infarction and ischemic stroke. The principal epidemiologic studies begun in the 1990s first examined the respiratory effects of atmospheric pollution and then focused on how pollution peaks affected cardiovascular risk. These studies used data from large metropolitan areas in North America and Asia as well as several large European cities to demonstrate the clear existence of a relation between air pollution and cardio- and cerebrovascular mortality. They also observed an increase in hospital admissions for myocardial infarctions and cerebrovascular accidents on days with high air pollution levels. The pollutants involved have not yet been clearly designated, but it appears that fine suspended particulate matter (PM2.5) and gaseous pollutants such as ozone appear to contribute strongly to these harmful effects. A complete analysis of these data shows the need for a thorough evaluation of the cardio- and cerebrovascular risks associated with air pollution, especially in French metropolitan areas. Precise identification of those at high risk from specific pollutants is essential to improve targeting of prevention strategies.