The incidence of atopic disease and its relation to the family history was studied by questionnaire in 1325 children, 7 years of age. A higher incidence of bronchial asthma (2.7%) was found than in a previous Swedish study. The total incidence of atopic disease in the children was 15.1% with a higher level when there was a double parental history of such disease (42.6%) as compared with a single such history (19.8%). When both parents had an identical type of atopic disease, i.e. respiratory or skin, the incidence of atopic disease was higher (72.2%) than when non-identical types occurred in the parents (20.8%). The findings support theories of a polygenic transmission of atopic disease as well as a genetic influence on symptom specificity in such disease and may be of value in genetic counselling.