Asthma is a chronic, inflammatory airway disease associated with airway obstruction by smooth [Page 315]muscle constriction, swelling of the mucosa, and excessive mucus production. Patients experience unpleasant respiratory sensations of shortness of breath (dyspnea), chest tightness, coughing, and/or wheezing. Episodic worsening of the disease (exacerbation) reduces patients’ quality of life and can be life-threatening with suboptimal treatment. Symptomatic episodes affect mood and energy levels and can lead to anxiety, fear, panic, irritability, and fatigue. The following paragraphs further introduce asthma pathophysiology, etiology, prevalence, and medical treatment; outline psychological and behavioral influences on asthma pathophysiology and management; describe comorbidity of asthma with psychological disorders; and outline treatment of asthma from a psychological and behavioral perspective.