During a review of 400 gastroscopies performed as a routine on patients with gastro-intestinal symptoms, it was unexpectedly observed that a group of patients who had a hypochromic anemia and achlorhydria had a definite atrophic gastritis gastroscopically. It is our purpose in this report to present support of our belief that idiopathic hypochromic anemia is the partial expression of a syndrome and not a disease entity, and that it is as yet an unknown metabolic disturbance in which atrophic gastritis plays a dominating rôle. This syndrome may be an etiologic factor in the genesis of pernicious anemia, subacute combined degeneration of the cord, and carcinoma of the stomach and esophagus. As Osler1originally showed in chlorosis, this syndrome is readily amenable to iron therapy, which will effect cure or marked improvement. Owing to the then unrealized occurrence of this syndrome, detailed studies of the erythrocytes, such as their diameter