During the last years, several sets of criteria for the diagnosis and classification of primary Sjögren's syndrome (SS) have been promulgated. So far none has achieved universal acceptance. It is conceivable that the lack of pathognomonic features of SS and the frequent coexistence of SS with other connective tissue di-seases partly explain the lack of agreement. Regardless of criteria preference the final diagnosis of SS should reflect the definition of the syndrome, being an inflammatory and autoimmune rheumatic disease. It is therefore suggested that any criteria employed should include a mandatory combination of measurements of exocrine dysfunction. histological confirmation of inflammation, serological evidence of autoimmunity and exclusion or diseases mimicking primary Sjögren's syndrome.