The clinical syndrome of border-zone ischemia is described in eight patients. Cerebral damage in four occurred during or after cardiac surgery and the other four patients had each experienced a period of severe hypotension. Cerebral blindness and visual disorientation are the most regular features and are produced by ischemic lesions in the parieto-occipital region, the common border-zone territory between all three arterial territories. Some patients show bibrachial sensorimotor impairment and a disturbance of volitional saccadic eye movement caused by more anteriorly placed ischemia in the anterior-middle artery border zone. Some show a temporary dyslexia/dysgraphia and memory defect related to bilateral parietotemporal lesions in the middle-posterior border zone.