We report on a family in which a mother and her 3 daughters have delayed psychomotor development and/or psychosis, hydrocephalus with white matter alterations, arachnoid cysts, skeletal anomalies consisting of brachydactyly, and Sprengel anomaly. Biochemical and cytogenetic analyses were normal on all 4 patients. The pattern of inheritance, clinical manifestations, and variability of expression suggest that this is a new hydrocephalus syndrome possibly transmitted as an X-linked dominant trait.