Introduction Cerebral lipoidoses are rare diseases, and clinical reports are needed to pool observations which will lead to a better understanding of the basic pathology. This paper is concerned with the report of Spielmeyer-Vogt's disease in 2 siblings (sister and brother). The descriptions by Benda,1 by Jefferson and Rutter,2 and in the symposium edited by Van Boegaert3 contain comprehensive reviews of literature concerning this disease. Case Material Family History.— A girl and a boy are brother and sister. The entire family consists of father and mother, both college graduates, and 5 children. The eldest, a girl now 16 years old, is in the upper 10% of all high school seniors on scholarship tests. She is farsighted and astigmatic and wears glasses. She has hay fever allergy, but no other known congenital or acquired disorders. The second child is the afflicted girl and the third child the afflicted