The results of operative treatment of scoliosis in Down syndrome at one institution are reviewed. Seven patients with progressive scoliosis who had undergone arthrodesis of the thoracolumbar spine were identified. Clinical and radiographic results were noted, as were any complications. Mean patient follow up was 9 years (range 2-25). All patients eventually showed radiographic evidence of solid fusion with no curve progression. One patient had undergone a revision procedure for pseudoarthrosis and failure of Dwyer instrumentation. Other complications included a lateral subluxation under the fusion area, pneumonia, and one asymptomatic hook dislodgment. Progressive deformities of the thoracolumbar spine in Down syndrome patients can be treated with fusion and instrumentation with cessation of progression. As is the case for upper cervical fusion in these patients, the complication rate is notable.