This is a condition whereby the lining of the gullet changes its appearance in response to long-standing and regular acid-induced damage. Barrett’s oesophagus is more common in patients with a long history of heartburn (especially if the symptom is frequent and occurs at night) and in patients with a hiatus hernia. The protective change (called metaplasia) is unfortunately associated with a slight increase in the risk of developing cancer and is therefore called a pre-malignant condition. It is important to realise however that the vast majority of patients with Barrett’s oesophagus die with it (i.e. from an unrelated condition) and not from it. Barrett’s oesophagus is diagnosed at upper gi endoscopy; it is not seen on X-ray studies such as a barium swallow or CT scanning.