Anterior spinal arthrodesis with instrumentation is a useful alternative to posterior surgery in the management of thoracolumbar deformity in the adolescent and young adult. In adults, flexibility of primary and compensatory curves significantly decreases with increased age and curve magnitude. Curve flexibility is an important determinant of postoperative outcome. Anterior surgery is most appropriate for patients with moderate thoracolumbar or lumbar curves and good flexibility of adjacent segments. Adult patients may develop early degeneration at primary and compensatory curves, and these curves should be evaluated carefully before surgery and monitored closely during the postoperative period. Good results can be obtained in well-selected patients with a rigid instrumentation system and anterior structural grafts.