Indoor air quality has gained significant attention in recent years, marked by several major initiatives, including the creation of the Indoor Air Quality Observatory (OQAI), the inclusion of several priority actions in the National Environmental Health Plans (PNSE) 1 and 2, the Grenelle 2 Act, and the development of specific indoor air quality guidelines (VGAI). The public health stakes are high because the entire population is exposed to pollutants present in the air of indoor environments. The resulting health problems are numerous and encompass a wide range of clinical manifestations, most of which are not specific to the detected pollutants. For some, such as environmental tobacco smoke, radon, and carbon monoxide, the health effects are well known. Furthermore, recent studies establish a link between poor indoor air quality and reduced performance in school and workplace settings. There is now strong demand for the establishment of thresholds for pollutants present in these enclosed spaces, and this initiative has been undertaken by AFSSET. Following a prioritization phase that identified 11 priority pollutants, a method for developing VGAIs was established, consisting, for each pollutant, of analyzing the robustness of available national and supranational VGAIs and VTRs to select the most appropriate one. Several VGAI were proposed based on exposure durations and the nature of the effects. Based on health criteria, they do not have the status of management values, particularly regulatory ones. The HCSP’s specialized commission on the environment, convened by the DGS, proposes “guideline values to assist in indoor air quality management.” The WHO has embarked on a similar initiative; its recommendations are expected to be released by the end of 2010. (R.A.)