We have conducted a series of studies on adult asthma in Singapore that describe the prevalence, morbidity and mortality and their relationships with environmental and medical care factors. There was no evidence of a temporal increase of mortality from 1976 to 1995 for adults. The prevalence rate of asthma is 2.4% in men and 2.0% in women. There is considerable morbidity among asthmatics, corticosteroids are under-used, and patients' knowledge and self-management skills is poor. Increased morbidity is significantly associated with current keeping of pets, current smoking, and the patients' knowledge and self-management skills. Occupational exposure contributes up to a third of asthma morbidity. Malays and Indians have higher rates of asthma mortality and morbidity than Chinese. They have greater exposures to airborne allergens from keeping rugs or carpets, and pets. Malays experience the most morbidity from asthma, but make less use of health services, and receive less medical attention, than Indians or Chinese.