Rationale: Acutely ill asthmatic African Americans come to Emergency Departments more frequently and are admitted to hospital more often than Caucasians but the reasons are unclear. Objectives: To determine whether such phenomena represent racial differences in attack severity and/or limited effectiveness of ₂ agonist therapy. Methods and Main Results: We contrasted clinical features, airflow limitation and albuterol responsiveness in 155 acutely ill adult African-American and 140 Caucasian asthmatics as they are presented to 8 emergency departments. Assessments were standardized across institutions using a care path, and admission and discharge decisions were made according to predetermined criteria. The degree of obstruction was measured by peak expiratory flow rates. The clinical features of both groups were similar. The African-Americans, however, had lower flow rates (P = 0.002) and more of them experienced severe or potentially life threatening episodes (P <0.001). Albuterol was equally efficacious in both populations and there were no differences in the post treatment flow rates achieved irrespective of the initial attack intensity. There were no racial differences in admission/discharge ratios. Conclusions: Our data indicate that African-American asthmatics tend to present with somewhat more intense attacks than Caucasians, but they respond equally well to routine treatment. Similarly, there were no racial disparities in hospitalizations when standard criteria are employed.