Barrett's esophagus (BE) is a complication observed in a small subset of patients with chronic gastroesophageal reflux. It is characterized by the presence of intestinal-type goblet cells in biopsies from the lower esophagus. The prevalence of BE increases with age, affecting 1% of the population older than 60 years. A genetic predisposition to reflux disease has been proposed. In a twin study of reflux disease, concordance was greater in monozygotic than dizygotic twins. An association between BE and esophageal adenocarcinoma, the incidence of which has increased remarkably in the last few decades, has been established. Esophagogastric junction cancers can arise from small areas of cardia intestinal metaplasia (CIM). Regular endoscopic and histologic follow-up of BE patients is recommended. Surveillance of patients with CIM is not advised. Chromoendoscopy may help to detect areas of high-grade dysplasia (HGD). The ablation of BE, e.g. by PDT or argon plasma coagulation, is not yet proven to reduce the cancer risk. Esophagectomy is still the standard management of HGD. Endoscopic mucosal resection may be used for visible, localized lesions with HGD, and this technique may be combined with thermal ablation for areas of HGD without visible abnormality.