A 69-year-old white man developed progressive symptoms of dysphagia for solids and liquids and regurgitation of undigested food accompanied by a 12-kg weight loss over a 4-month period. Initially, radiographs of the esophagus and stomach were normal, but when repeated 4 months later, a diagnosis of achalasia was suggested. Esophageal manometry performed at that time demonstrated a motor abnormality of the esophagus and lower esophageal sphincter consistent with a diagnosis of achalasia. Upper endoscopy revealed a small ulcerated tumor in the cardia of the stomach. A biopsy specimen was interpreted as adenocarcinoma of the stomach. Surgical treatment included resection of the gastric tumor along with a 4-cm segment of the distal esophagus, resection of a collar of apparently uninvolved stomach, and esophagogastrostomy. Nine months following surgery the patient was restudied. An upper gastrointestinal roentgenogram demonstrated a return of esophageal caliber and configuration to normal. Manometry showed that esophageal contractions had reverted to a normal progressive, postdeglutition pattern throughout the length of the esophagus. This is the first report in which achalasia secondary to gastric adenocarcinoma was reversed after tumor resection.