The reasons for significant disparities in asthma mortality are unclear. Maryland vital statistics and medical examiner data were used to examine timing, location, and circumstances of asthma deaths. We found that unexplained deaths increased substantially over the past 10 years and that young, male, and black asthmatics were more likely to die before hospital admission. Factors contributing to disparities included better availability of anti-inflammatory medications among whites versus blacks, and a higher incidence of positive toxicology screens among males versus females. Disparities in asthma mortality might be reduced through efforts to optimize asthma treatment and reduce illicit drug use.