Aicardi syndrome is characterized by agenesis of the corpus callosum, infantile spasms, and ocular anomalies. Very few morphologic descriptions have been made of the central nervous system of children with this syndrome. We performed a postmortem examination of the brain of a 13-year-old girl with clinically well-documented Aicardi syndrome. Gross examination revealed a small brain (745 g) with the right cerebral and cerebellar hemispheres smaller than the left. There was agenesis of the corpus callosum, and ectopic gray matter was scattered throughout the cerebral hemispheres. Both choroid plexus and arachnoid cysts were present. Microscopic examination revealed indistinct cortical layering and multiple foci of ectopic gray matter. The cerebellar sections were altered by focal atrophy with gliosis and Purkinje cell dropout. Multiple sections of cerebrum contained astrocytes with coarse, paranuclear, eosinophilic inclusions. Electron microscopy, immunohistochemistry, and special stains further defined these inclusions, which we speculate represent a degenerative process.