A cerebral aneurysm is a weak or thin spot on a blood vessel in the brain that swells and fills with blood. Rupture of a cerebral aneurysm, known as aneurysmal subarachnoid haemorrhage, is a medical emergency and is associated with increased mortality. This article explores the anatomy and physiology of the brain and blood vessels. Current research and guidelines are used to highlight risk factors for cerebral aneurysms and their rupture and to discuss best practice for treating both. The article provides information on the management and complications of the condition, alongside nursing considerations, long-term care, discharge and rehabilitation.