Sjögren's syndrome is a chronic inflammatory disease of unknown origin. Its major features are total or decreased salivary and lacrimal gland output resulting in oral and ocular tissue changes, swelling of the parotid glands, and chronic rheumatoid arthritis, but not all of these features need be present simultaneously for the diagnosis to be made. The disease is most common in middleaged women, although it has been reported in both young and old women and occasionally in men. The possible relationship and similarity of the condition to Mikulicz's disease and to collagen disorders have been mentioned. At present there is no satisfactory treatment for the entire symptom complex, and therapy is directed instead at alleviation of individual symptoms.