Over the last decade, the search for an alternative to primary fetal material for use in cell replacement therapies for neurodegenerative disorders has led to an increasingly enthusiastic interest in neural stem cells. This thesis attempts to determine the usefulness of cerebellar neural stem cells for the repair of disorders such as the hereditary ataxias, which affect specific cells of the cerebellum, aided by the development of a novel in vitro model of cerebellar damage in the rat.