Pulmonologists are physicians who specialize in treating the respiratory system, and some pulmonologists sub-specialize in specific conditions, such as asthma or chronic obstructive pulmonary disorder (COPD). For patients who have serious or chronic breathing problems, pulmonologists often work in hospital settings. If they feel it may benefit your asthma treatment, your pulmonologist may refer you to other asthma specialists, such as respiratory therapists. Allergist-immunologists also specialize in asthma, as well as in allergies. Pulmonologists have had years of additional training in this field and are more experienced in asthma treatments and management than non-specialists. Part of their focus is dealing with asthma, so they are the best experts to see in hospital care.