As a result of a 1990 survey by questionnaire, the symptoms of atopy among all 4,952 school children aged 5 to 16 years in the municipal district of Viborg, Denmark, were registered. Random checks, made among children who were recorded as having symptoms, and others who were recorded as having none, accorded well with the information supplied by the parents about symptoms and the clinical diagnosis of a specialist; 10.5% of all school children had rhinitis, 7% had atopic eczema, 3.2% had urticaria and 4.5% had asthma; 1/4 of all those questioned had shown symptoms within the last year, and a further 13% of all the children were reported as having had atopic symptoms that had disappeared more than a year previously. Of the children showing symptoms within the last year before the survey, 2/3 had gone to a doctor. Of the children with present symptoms, largely asthma, 1/4 had been referred to a hospital allergy clinic. For 1/3 of the children with present symptoms, these had led to no contact with a doctor. Of the cases with present symptoms, 6.5% had had contact with natural healers or chiropractors. Rhinitis and asthma were most frequent among boys, while atopic eczema was most frequent among girls. For both sexes, the frequency of rhinitis increased during their years at school, while the frequency of skin symptoms fell.