During the 1970s and 1980s, the implementation of control measures within a new legislative framework and the development of a nuclear power program led to a significant reduction in the concentrations of major air pollutants resulting from industrial emissions and heating. Pollution caused by the movement of goods and people is now predominant, particularly in urban areas, and motor vehicle traffic has become one of the main contributors to the health impacts of urban pollution. Although pollution levels in most French cities are not “alarming,” certain pollution indicators are gradually increasing (NOx and O3). Alongside this fundamental shift, winter and local pollution spikes are giving way to summer smog or more complex and diffuse forms of pollution, rich in hydrocarbons, nitrogen oxides, oxidizing compounds, and very fine particles. In France, as elsewhere in the world, air pollution has changed radically since the 1970s. In terms of public health, the main question today is what impact the currently observed levels of ambient pollution have on the health of the population.