A study of 87 cases of carcinoma involving the gastro-oesophageal region included seven cases of adenocarcinoma confined to the anatomical limits of the oesophagus. Six of these intraoesophageal adenocarcinomas appear to have arisen in "oesophagi lined by columnar epithelium". The seventh, a carcinoma of double histological pattern associated with a sliding hiatus hernia, showed a complex mixture of epithelial structures in the lower oesophagus. The histogenesis of intraoesophageal adenocarcinoma is discussed, and it is stressed that its prognosis may be relatively favourable.