Anatomy, pathophysiology, epidemiology, and disease characteristics link the upper and lower airways. Nonspecific symptoms such as cough, congestion, shortness of breath, and recurrent infection may be related to the upper airway, lower airway, or both. Patients with the most severe disease often exhibit symptoms and findings of inflammation at both sites. Recent literature suggests that medical treatment and, when appropriate, surgical therapy directed at the upper airway can yield improvements in the lower airway. An understanding of the diagnosis and management of diseases at both sites will afford patients the best possible outcomes.