Proton pump inhibitors have changed the management of acid-related upper gastrointestinal disorders. Other effective strategies for reducing upper gastrointestinal morbidity include lifestyle modification, Helicobacter pylori eradication for patients with present or past peptic ulcer disease and infection, and less potent therapy for mild dyspepsia and gastro-oesophageal reflux. Proton pump inhibitors have a definite role in the prevention of recurrence of oesophageal strictures. They can also be used to prevent the ulcerative complications of non-steroidal anti-inflammatory drugs in patients at high risk. In Barrett's oesophagus the efficacy of proton pump inhibitors in preventing disease progression and the development of adenocarcinoma is unclear.