Tc-99m pertechnetate scintigraphy was performed in a patient with Barrett's esophagus and a history of previous lye ingestion. Radionuclide uptake was present in the distal two-thirds of the esophagus and persisted after the drinking of water. This technique is simple and accurate and may be of significant benefit in determining the presence and extent of Barrett's esophagus, which carries an increased incidence of adenocarcinoma development. Examination of patients with chronic gastroesophageal reflux, using this technique, is advocated.