Space occupying supratentorial ischemic stroke has a high mortality. The benefit of decompressive surgery in these patients is still matter of debate. In a prospective study we performed craniectomy in 37 patients with acute middle cerebral artery infarction and progressive deterioration under conservative antiedematous therapy. Twenty-one patients treated conservatively during the same period served as control group. All survivors were reexamined between one to two years after surgical decompression. In addition, neuropsychological tests were performed, including an Aachener Aphasie Test (AAT) in those patients with infarction of speech-dominant hemisphere. Clinical evaluation was graded using the Barthel index (BI). Mortality rate in the operated group was 37%. Twenty-three patients survived acute stroke and were reexamined. Despite complete hemispheric infarction, no patient suffered from complete hemiplegia or was permanently wheel chair bound. In speech dominant hemispheric infarction (n = 8) only mild to moderate aphasia could be detected. Mean BI was 64. Mortality rate in the conservatively treated group was 76%. The clinical outcome following craniectomy for the treatment of severe ischemic hemispheric infarction is unexpectedly good. Therefore, decompressive surgery should be considered in cases of space-occupying hemispheric infarctions and conservatively uncontrollable intracranial pressure.