Hereditary multiple exostosis (HME) is an autosomal dominant disorder characterized by multiple osteochondromas. We describe a case of acute cervical spinal cord compression arising from an exostosis at the lamina of C7 and T1 in a 4-year-old Mexican-American boy with HME. His affected sibling also displayed spinal cord compression because of a bony exostosis. Acute cervical spinal cord compression resulting from osteochondroma is a serious complication of HME. © 2010 Wiley-Liss, Inc.