Severe asthma is a heterogenous disease, and patients present with a variety of clinical histories, physiologic changes (beyond changes in forced expiratory volume in one second), and airway inflammation. That’s why Dr. Sandra Adams is joined by Dr. Linda Rogers, Clinical Director of the Asthma Program at the Icahn School of Medicine at Mount Sinai, to discuss how we can better differentiate difficult-to-control and severe or refractory types of asthma.