This survey of acute asthma admissions points to a number of factors that may be relevant to the continuing asthma mortality at home and in hospital. 1. Complications in hospital occur with increasing frequency with increasing pulse rate, but mortality is low with intensive management. 2 Young patients tend to have the higher pulse rates and greater risk of complications. 3. Many patients with severe asthma do not receive adequate drug treatment, particularly corticosteroids, from their general practitioners before admission to hospital. 4. Many severe attacks of asthma come on quickly and these patients are particularly at risk.