The purpose of this study was to explore patient perceptions of asthma severity and danger from asthma, correlate them with objective measures, and assess the impact of psychologic variables on the perception of severity. Recognition of patients at greatest risk for fatal attacks requires identifying those with severe asthma. In our study of 95 adults with asthma, we found that the subjective factors of perceived severity and perceived danger and the objective factors of medications, hospitalizations, history of intubation, and pulmonary function were important markers of asthma severity and risk. Our findings indicate that asthmatic adults make independent self-assessments that generally correlate with objective markers of increased risk of mortality and increased severity of the asthma. The perception of high severity was significantly correlated with depression, panic-fear, frequency of emergency department visits, and with an objective index of risk of death. The latter includes variables obtainable from history alone (number of medications to control symptoms, need for prednisone, prior intubation, and prior recent hospitalization) and is correlated with spirometric indexes of airflow obstruction, occurrence of nocturnal symptoms, and number of emergency department visits.