Biopsy specimens from the antral and body mucosa of 183 patients with gastric polyps (adenoma, 4; hyperplastic polyp (HP), 52; foveolar hyperplasia (FH), 49; and inflammatory polyp (IP), 78 cases) have been examined. The prevalence of gastritis in the series was compared with that in 183 age- and sex-matched controls. The dynamics (progression) of gastritis was evaluated by means of an age-adjusted gastritic score. In the HP and FH groups the prevalence and progression of body gastritis were significantly higher and more rapid (p less than 0.001) while the prevalence of antral gastritis was lower (p less than 0.05) and its progression less rapid (p less than 0.001) than in controls. It is concluded that the pernicious anaemia type of gastritis (A-type gastritis) is closely related to gastric polyps of hyperplastic origin. The progression of this gastritis type seemed to increase in the order IP, FH, and HP. In addition, we observed an increase in the prevalence of intestinal metaplasia (p less than 0.001) and marked epithelial dysplasia (0.1 greater than p greater than 0.05; chi-square = 3.75) in stomachs with polyps as compared with in controls.