Traumatic rupture of the aorta is a major cause of morbidity and mortality in rapid deceleration road traffic accidents, with an immediate mortality of 85%. Of the 15% that survive the initial injury, approximately 50% will die within 24 h if left untreated. Prompt diagnosis and early surgical treatment are necessary if such patients are to survive. Aortography is the standard investigation of choice and provides a rapid, sensitive test of aortic rupture. Other modalities, such as plain chest radiography, computed tomography (CT) and ultrasound may also play a role in diagnosis. Magnetic resonance imaging (MRI), with its multi-planar imaging capability, is now widely used for imaging non-traumatic disorders of the aorta. However, its use in traumatic rupture has been limited by difficulties in monitoring and in access to the patient during the scan. We present a patient who survived the initial injury, when the diagnosis of aortic rupture was not suspected. and presented 3 weeks later with chest pain. An MRI scan was feasible as the patient was haemodynamically stable, and it provided an elegant non-invasive means of diagnosis, so that aortography was not necessary in this case. Although aortography is likely to remain the investigation of choice in the acute situation, MRI is a useful alternative in selected cases.