Summary 1. A classification of the commoner abdominal vascular accidents is presented. 2. Case reports indicating the different types of vascular catastrophes are recorded. 3. Emphasis is placed on some of the more insidious forms of vascular lesions which may present a problem in the diagnosis of abdominal pain. 4. The radiological signs of leaking abdominal aneurysm and dissecting aneurysm are discussed. 5. The radiological features of venous mesenteric thrombosis are discussed and the clinical findings compared with those of arterial mesenteric thrombosis and means of differentiation.