Pulmonary Medicine is the medical specialty dealing with diseases involving the respiratory tract and lungs. Pulmonology is considered a branch of internal medicine, and is related to intensive care medicine. Pulmonary Medicine, Critical Care Medicine and Sleep Medicine specialize in the diagnosis and treatment of patients with illnesses that affect the lungs, breathing and sleep. A Pulmonologist is a medical doctor who specializes in treating disorders related to the lungs and respiratory system. Pulmonologist are also known as chest disease specialist, respiratory specialist, chest physician.