The authors describe 14 personal cases of progressive supranuclear palsy, 8 of them including a neuropathological study. The analysis of this material confirms the characteristics of this nosological entity, which is now well individualized amongst the apparently idiopathic degnerative diseases of the CNS. The clinical picture was characterized in all cases by a supranuclear opthalmoplegia, a pseudo-bulbar syndrome, an axial dystonia and a 'subcortical' dementia of a particular type. The average duration of the disease was 4 years for the 12 patients followed until death; the first symptoms appeared at a slightly older age than the average reported in the literature. Males are not predominantly affected in our material. Lesions are remarkably homogeneous as to their localisation in all cases but one. The nuclei of cranial curves are moderately involved, the reticular substances throughout the brain stem is more severely effected. In two cases, senile degenerative lesions of the cerebral cortex are associated with subcortical lesions of the progressive supranulcear palsy. No anamnestic or histologic feature is suggestive of any etiology of this disease. L-Dopa with or within a Dopa-decarboxylase inhibitor did after alter neither the patients condition nor the course of the disease.