Arefractory asthma is an uncommon disease (likely < 5% of total asthma), it is poorly understood and, therefore, often frustrating to treat. What follows is the proceedings of an American Thoracic Society (ATS)-sponsored workshop. The participants hope it will serve as an aid to begin to define, understand, and manage these refractory patients. Perhaps more importantly, it is also hoped that these proceedings will highlight the many questions that remain, and eventually lead to improved outcomes.