The incidence of cerebral infarction amongst patients <45 years ranges from 3.4 to 11.3 per 100 000. Aetiology of cerebral infarction is more heterogeneous amongst young patients than amongst older patients including frequent dissection of neck vessels. Because of longer expected survival, prognosis is of special importance amongst younger patients. Average annual long-term mortality rate after the first year of cerebral infarction ranges from 0.6% to 1.8% and is about 10 times higher than amongst matched controls. Long-term mortality is associated with cardiac embolism and atherosclerosis, whilst dissection of neck vessels is associated with low long-term mortality. Average annual long-term recurrence rate of cerebral infarction ranges from 0.3% to 1.7% after the first year. Recurrence of cerebral infarction and other vascular events is highly associated with traditional risk factors including smoking, diabetes mellitus and symptomatic atherosclerosis. Dissection of neck vessel is associated with low long-term mortality rate and low recurrence rate of cerebral infarction. Tailoring secondary preventive treatment according to aetiology and risk factors suggests better prognosis.