The circumstances surrounding all deaths from asthma in New Zealanders under 70 years of age between August 1981 and July 1983 have been analysed from information recorded or recalled by doctors or relatives of the deceased. Factors which may have reduced the time available for effective treatment of these severe attacks are described to draw attention to ways in which mortality might be reduced. For almost half of the 271 deaths medical help had not been called before the patient was in extremis. When medical help was summoned in sufficient time doctors commonly did not give corticosteroids or used them inadequately. Difficulties in using medical care and noncompliance with asthma management were common particularly in Polynesian patients. In 38% of patients some medical inadequacy appeared to contribute to poor long-term care and education. Failure of patients to attend for ongoing medical care, education and preventative treatment, or a medical failure to deliver these may have led to chronically reduced lung function. Any further deterioration may then have more rapidly led to a fatal outcome. Lack of patient or family awareness about how to detect and cope with an unusually severe attack was found and contributed to avoidable fatalities.