Asthma remains the second most common cause for admissions to a paediatric hospital bed. The aim of this study was to describe the characteristics of children admitted to hospital with an acute asthma attack and to identify factors that may prevent future hospital admissions. Parents of all children aged 3 to 15 years admitted to hospital for acute asthma were interviewed and the child's case record reviewed. Children were recruited consecutively in two groups: 141 summer/autumn and 125 winter/spring 1996. According to the pattern of symptoms in the previous 12 months, 61% of the children had infrequent episodic asthma, 26% had frequent episodic asthma, and 13% persistent asthma. Only 8% of children aged 8years or less had persistent asthma, in contrast to 22% of those aged > 8 years. There was evidence of both inadequate prescription of preventive treatment and poor compliance in the frequent episodic and persistent asthma groups. Of the whole group, 44% had previously been given an acute asthma management plan, but only 9% of them used it before the current hospital admission. There was a delay in seeking medical advice (> 24 hours after the onset of symptoms) in 27% of all admissions. This study has identified potential areas where intervention may reduce the number of future admissions.