All the 7 year old schoolchildren in North Tyneside were screened for wheeze with a questionnaire followed by selective clinical assessment: 9-3% of the children had had episodic wheeze within the past year and all those followed up subsequently responded to one or more of the drugs used for asthma. A further 1-8% had had similar symptoms since starting school, though they had not wheezed in the past year. Frequency of symptoms in the 11% of children with features of asthma varied widely and correlated with bronchial reactivity on histamine challenge, but it was not possible to separate children with frequent wheeze from asymptomatic controls by their response to histamine. It was concluded that all these wheezy children had symptoms of a common basic disorder and that they should all be treated as asthmatic.