Peptic ulcer disease (PUD) collectively refers to the ulceration of the mucosa of the stomach or duodenum. An ulcer is a breach in the epithelium that penetrates the muscularis mucosae. National hospital data show that 10% of patients having endoscopy have a peptic ulcer; 25% of patients have a serious complication such as bowel obstruction, haemorrhage, perforation or gastric outlet obstruction. There is also an increased risk of gastric malignancy. This article looks at the presentation, causes and management of PUD in general practice.