Pulmonology is the subspecialty of Internal Medicine that involves the diagnosis, treatment, and prevention of lung diseases. A lung specialist is often asked to evaluate and treat patients who have shortness of breath, emphysema, asthma, chronic cough or, chronic infections of the lung. Not everyone who suffers from lung disease needs a Pulmonologist. Many patients with asthma and pneumonia, etc., can be managed by an internist.

A lung specialist's skills are most needed in those complex cases which require special knowledge in diagnosis and treatment of lung disease or in those cases in which highly specialized tests are needed for diagnosis. One of the major activities of the pulmonologist is the care of intensive care patients who require ventilatory support on a respirator. Another is in the diagnostic evaluation of lung problems with the fiberoptic bronchoscope.