The clinical problems posed by a series of partial or total monolateral carotid occlusions complicated by cerebral infarction are discussed. Emphasis is laid on the frequent aspecificity of the symptomatology, the inconsistency of palpatory and auscultatory findings in the cervical region, and the value of certain medical techniques that may precede angiographic diagnosis. Considering the lack of reports in the literature, a case in which carotid stenosis was considered to be of luetic nature is noteworthy. Prophylactic treatment designed to prevent another cerebral attack hinges essentially on the correction of arterial hypertension and on the use of antiaggregating drugs. Endarterectomy is contraindicated by the presence of limiting factors.