We compared the epidemiology of Barrett's esophagus in Japan and the West. Japan GERD Society Study Committee conducted the epidemiological survey in 2,595 patients who underwent endoscopy the first time, confirming that Barrett's mucosa was observed in 536 patients (20.8%) out of 2,577. But Barrett's esophagus (>3 cm of columnar lined epithelium) was detected only 5 (0.2%). The prevalence of typical Barrett's esophagus was markedly low in Japanese compared with Westerners. In Western, the incidence of Barrett's esophagus has increased markedly since the 1970s. It is estimated that Barrett's esophagus is found in approximately 6-12% of patients undergoing endoscopy for symptoms of GERD and in 1% or less of unselected patient populations undergoing endoscopy.