Barrett's esophagus occurs more frequently than previously anticipated. Detection of Barrett's esophagus is by endoscopic biopsy in which normal squamous epithelium of the esophagus is replaced by a specialized columnar epithelium of any length. Patients with more than five years of gastroesophageal reflux symptoms, particularly those 50 years of age or older, should have upper endoscopy to detect Barrett's esophagus. With recognition of Barrett's esophagus as a premalignant lesion, the crucial issue is surveillance for detection of dysplasia. Although the natural history of dysplasia is incompletely defined, it is clear that patients with dysplasia have a higher risk for adenocarcinoma than those without dysplasia. Dysplasia is not the ideal marker for selecting patients at high risk for adenocarcinoma, however; recent studies have shown that p53 protein accumulation appears to be earlier and more specific/sensitive marker of malignant potential in Barrett's esophagus. Management of Barrett's esophagus often involves a multidisciplinary evaluation and its current status is reviewed.