BACKGROUND: Indoor air pollution (IAP) that constitutes a major global public health problem requiring increasing efforts in research and policymaking and it may have special significance for elderly that are likely to spend most of their day indoors and appear to be particularly susceptible to adverse effects of chemical pollutants and bio-contaminants. Yet, evidence existing on the effects of IAP in elderly is scanty. The Geriatric study in Europe on health effects of air quality in nursing homes (GERIE) study aims to assess health effects of major indoor air pollutants and thermal conditions in elderly (> 70 years) living stably in nursing homes (NH) across Europe. Respiratory effects were particularly considered as airways and lung constitute the first target of air pollutants.Objectives: We describe here the rationale and the methods of the GERIE Study. METHODS: 8 nursing homes were randomly selected in 7 European countries. Twenty individuals were randomly selected in each nursing home, 20 individuals were randomly selected. Major indoor and outdoor air chemical pollutants (PM10, PM2.5, PM0.1, formaldehyde, NO2; O3, VOC, CO2) and bio-contaminants (moulds, allergens) were assessed objectively with standardized procedures. Major health status indicators were assessed through a standardized questionnaire, non-invasive clinical tests and blood and urine biomarkers as well as saliva for ADN. RESULTS: The GERIE study has given the opportunity to publish two reviews on respiratory health effects of indoor and outdoor air pollution in elderly. In addition it has provided the inventory of air quality and thermal conditions in 50 nursing homes across Europe and data on respiratory health status in 600 elderly aged 82 years in mean. Major future results will include the relationships between NH environment and health in elderly. CONCLUSIONS: The main long-term purpose of the GERIE study is to improve the health of elderly who permanently reside in nursing homes or of those who are exposed to indoor air pollution because of reduced mobility.