Schatzki first reported a ring-like structure at the esophagogastric mucosal junction in 1953. There is still no uniform agreement as to its exact location, etiology, or clinical importance. We found an esophagogastric ring in 15% to 18% of 22,368 patients having routine upper gastrointestinal examinations. It was present only in patients with cephalad displacement of the esophagogastric junction and only in those who had sharply and circumferentially marginated transition of esophagogastric mucosal junction. It is postulated that the esophagus shortens on vagal stimulation by contracture of the longitudinal esophageal muscle, which causes a mucosal infolding at the esophagogastric junction. In a small group of these patients, fibrosis apparently develops in this region and results in a fixed organic circumferential diaphragm, which may cause obstructive symptoms. These concepts affect therapeutic alternatives.