The general pathology and clinical picture of cerebral venous thrombosis have been well recognized entities since the 19th century. But from our own experience of 92 cases, and from the study of cases reported in the literature, it is obvious that the diagnosis of cerebral venous thrombosis could be made with reasonable certainty only in a very few cases at the onset of the illness. In the great majority of the cases the correct diagnosis was revealed by the subsequent course of events. The cases associated with childbirth are usually best known and the easiest to diagnose. The fact, described by Symonds²⁰⁾, that increased intracranial pressure associated with ear disease is due to venous thrombosis is recognized in some cases as “otitic hydrocephalus”. But in the great majority of cases the diagnosis remains difficult when the symptoms first begin to manifest themselves. The study of our case material has been undertaken with a view to showing whether cerebral angiography has a special diagnostic value at the onset of the disease. Since the introduction of modern chemotherapy and treatment with anticoagulant drugs, an accurate diagnosis is extremely necessary from the onset of symptoms. Furthermore, the role of surgical intervention must be carefully evaluated. Only by early introduction of these therapeutic means will the situation improve to the point that the prospects of more or less complete recovery are fairly good. Experiences detailed herein are described from a purely clinical point of view.