Low-grade gliomas are the most common histological type of pediatric brain tumor. They can arise in any part of the nervous system. Although low-grade gliomas are slow growing, they often recur or progress, especially in areas such as the diencephalon or brain stem, where resection is limited by proximity to vital and eloquent structures. Radiation has been used to treat progressive low-grade gliomas, but it is not clear that it improves long-term outcome. Radiotherapy also has potential significant cognitive, endocrine, and vascular side- effects. There is a growing body of evidence to suggest that chemotherapy can delay and may obviate the need for radiation therapy or aggressive surgery. This chapter reviews the published chemotherapeutic trials. Chemotherapy appears to have a major role in the management of children with progressive low-grade gliomas.