The purpose of this study was to describe gender differences in asthma in a managed care organization. We collected data from a patient survey, electronic administrative data, and hard-copy chart reviews. Women reported significantly lower general health status, more symptoms and greater severity of asthma, more activity limitations, more use of asthma-relieving medications, and more acute visits for asthma than men. Conversely, women tended to report better asthma care measures. These gender disparities warrant further study to support appropriate adjustment of clinical care and health-care-related services for women.