In a survey of asthma among schoolchildren, a questionnaire was sent to the parents of 10,527 children aged 7-16 years. A group of 420 children with asthma was thereafter identified. Their asthma symptoms had caused little absence from school (none in the past 6 months in 60% of the group, and greater than 5 days in only 13%). During the preceding year 40% of the group had had more than 10 days of restricted physical activity due to asthma. Severe symptoms due to undertreatment were uncommon. Although 68 children were receiving no medication, most of them appeared to have only mild symptoms, and the parents requested aerosol inhaler in only ten cases. Symptoms at school were usually related to sporting activities. In 40% of the total asthma group the symptoms were unknown to the school health service before the survey. Dissatisfaction with the service was expressed by 24% of the parents of asthmatic children.