A patient is described with a mycotic abdominal-aortic aneurysm that was caused by Salmonella typhimurium, who presented to hospital four months after a urinary-tract infection that was caused by the same organism. The urinary-tract infection may have resulted from an episode of transient salmonellal bacteraemia, the significance of which was not appreciated. The pathogenesis, clinical features, treatment and prognosis of arteritis due to Salmonella species are reviewed. The early diagnosis and appropriate treatment of salmonellal mycotic aortic aneurysm is vital for a satisfactory outcome.