Of 89 patients with arteriovenous malformations of the brain, 47 were conservatively treated, nine of these died (19%), four with the first bleed, five of recurrent bleeding. Of 42 surgically treated patients, five died, a mortality of 12%. Four of these deaths occurred with patients in a deteriorating clinical condition caused by large intracerebral haematomas. The fifth death occurred with a recurrent bleeding where a ligation of feeding artery was the only treatment. There were no deaths in those patients in good clinical condition who underwent an excision of the malformation. Total excision of arteriovenous malformations should be performed whenever possible.