The relationship between home dampness and respiratory health was studied in two populations of children of 6-12 years old, living in the south east of the Netherlands. In one study, lung function was measured at the schools, and in both studies, information on respiratory symptoms was collected from a self-administered questionnaire completed by the parents of the children. Information on home dampness was collected by questionnaire. Information on other potential indoor determinants of respiratory health, like (sources of) nitrogen dioxide and smoking in the home was collected by questionnaire as well. Respiratory symptoms were found to be associated with home dampness. There was a weak, negative association between MMEF and reporting of mould in the home. Several potential biases were evaluated. It was not considered likely that the results could be explained by information, selection or confounding bias. However, further work is needed to conclusively exclude these biases, and to develop objective measures of home dampness for use in epidemiologic studies.