Dyspnea is a subjective sensation of breathlessness. This distressing symptom is experienced by many patients with lung cancer and often is accompanied by physiologic signs and symptoms, such as tachypnea, tachycardia, pallor, and cyanosis. Dyspnea-induced hypoxia may occur and cause confusion, cognitive impairment, and restlessness. Prompt and accurate nursing assessment of dyspnea can assist in identifying appropriate treatment interventions. Supplemental oxygenation and medications, along with treatment of the underlying cause of the dyspnea, may promote patient comfort. Nurses need to be skilled in assessing dyspnea experienced by patients with lung cancer and knowledgeable in implementing effective symptom management techniques.