This article explores the measurement, physiology, and clinical applications of lung volumes in diagnosing and managing pulmonary diseases. It details methodologies like spirometry, body plethysmography, gas dilution, and radiological techniques, emphasizing their role in conditions such as COPD and interstitial lung diseases. Key topics include lung compliance, hyperinflation, and gas trapping. Emerging technologies like the portable Minibox + improve accessibility. Accurate lung volume assessment aids in distinguishing restrictive and obstructive patterns, guiding interventions like lung volume reduction therapy. The article underscores the importance of quality control, proper interpretation, and integration with spirometry for effective respiratory disease management.