The cytologic features of dysplasia and carcinoma of the stomach are still poorly defined. In a series of 90 cases, a precise correlation could be made between smears and histologic data. Cytology was sensitive enough to allow characterization of: (1) active repair/regeneration, associated, in a number of cases, with intestinal metaplasia (slight dysplasia); the cellular atypia is minimal; (2) true dysplasia (formerly moderate and severe); this preneoplastic state is characterized by cellular atypia within clusters; and (3) true carcinomas (intestinal or diffuse type); classic criteria for malignancy are present, with a prominent lack of cell cohesiveness, though distinction from dysplasia may be very difficult. The advantages of cytology are the survey of large mucosal areas, investigation of the cardial region, not always accessible to endoscopic biopsy, and exploration of large ulcers. With the adjunct of cytology, the specificity and sensitivity of endoscopy plus histology clearly increase.