Duodenal ulcer is a common disease which places heavy demands on health care costs. The aetiology is unknown, but its pathogenesis is related to acid secretion. The characteristic symptom is chronic epigastric pain which precedes meals, occurs one to three hours after food, and one to two hours after retiring. The pain is relieved by food or antacids. Barium meal remains the prime investigation, but flexible endoscopy allows accurate visualization of the ulcer particularly in a scarred deformed duodenum. Complications include haemorrhage, perforation and obstruction. Time-honoured therapy including diet, antacids and anticholinergics simply relieves pain, whilst newer drugs (Tagamet, De-Nol, and Duogastrone) are effective in healing the ulcer. Surgery is indicated for complications or inadequately relieved pain.