[en] After an overview of the issue of air pollution (definition, pollutant emission, population exposure, main air pollutants and emission sources, assessment of air quality in France), this report discusses the various impacts of air pollution on health and their related costs: pathologies associated with a bad air quality, categories which are more exposed than others, assessment of health impacts of air pollution, health costs. The next part describes the current policies aimed at improving air quality: European and international commitments, national policy, public policy tools, impacts of policies of struggle against air pollution by some pollutants, current researches and knowledge to be improved