Relapsing polychondritis is a progressive multisystem disorder that predominantly affects cartilage, producing an inflammatory reaction. We present case histories from four patients having mainly respiratory symptoms in whom we measured the coronal diameters of the trachea and compared them with the tracheal measurements from radiographs of patients with no respiratory symptoms. The results showed that the disease produced diffuse narrowing of the main airway in all four patients. Early detection of tracheal narrowing is important, as patients presenting with respiratory tract disease have a worse prognosis than those who develop it later in the course of their illness. Other features of the disease are also discussed with reference to the cases presented.