Recent years have seen major advances in the understanding of motor and nonmotor operations of the cerebellum, including its role in cognition, and important discoveries in the genetics of the cerebellar ataxias. This comprehensive text on the cerebellum and its disorders ranges from embryology and basic neuroanatomy to a thorough survey of the sporadic and hereditary disorders of the cerebellum. Models of cerebellar function and clinical-pathophysiological correlations are thoroughly covered, and there is an extensive and authoritative review of recent advances in the genetics of cerebellar diseases. The chapters are written by the leading international authorities on the cerebellum.