THe records of 78 young adults, who had suffered cerebral infarction, were reviewed with regard to possible pathogenetic mechanisms. Atherosclerosis risk factors appeared to play a major role between the age of 40 and 50, especially in males. Non atherosclerotic factors of cerebral ischemia were found predominant among females under 40, owing to contribution of migraine, oral contraceptive use and pregnancy/puerperium. In 18% of the patients no etiology could be identified.