Almost a century after Little1 described the clinical syndrome now classified under the general term "cerebral palsy" the problem of etiology in a large number of cases remains enigmatic. This is complicated by the fact that cerebral palsy is not a distinct pathological or clinical entity and may result from numerous causes operating in the prenatal, natal, or postnatal periods of development, affecting different parts of the central nervous system and giving rise to different types and varying degrees of involvement. Our approach to the study of the hereditary aspect of cerebral palsy was to collect family histories at the Moody State School for Cerebral Palsied Children with special reference to families with more than one cerebral palsied child. In the course of this investigation a family group with two (Fig. 1) affected children, a boy (Fig. 2a) and a girl (Fig. 2b), came to our attention.