THE ANTERIOR APPROACH to the thoracic and lumbar spine for neoplastic disease is now a well-accepted procedure, with results, for the most part, superior to those achieved with laminectomy. However, the specific indications for anterior decompression and the selection of reconstruction techniques based on the location and extent of bony destruction have received surprisingly little attention. The authors report their experience with the operative management of 33 patients with benign and malignant tumors of the thoracic and lumbar spine, using the anterior transthoracic or retroperitoneal approach. The role of stabilization and the relative indications for anterior or posterior instrumentation are emphasized. The mean age of patients was 58 years. Twenty-three patients were male. Five patients had benign tumors, and the remainder had a variety of metastatic lesions. Twenty-nine patients had lower extremity motor deficits, although 25 were ambulatory preoperatively. Thirty-seven noncontiguous resections were performed in 33 patients. In 13 patients, the resected vertebral body was replaced with acrylic or bone without instrumentation; in 18, the acrylic was supplemented with anterior instrumentation; and in 6, both anterior and posterior instrumentation were used. Above T11, vertebral reconstruction techniques were used to restore stability after decompression. Between T11 and L4, anterior instrumentation was used to supplement vertebral reconstruction in all patients. Supplemental posterior instrumentation was used for three-column involvement. Motor function was stabilized or improved in 94% of patients, and 88% of patients were ambulatory postoperatively. Of 28 patients with malignant disease, 23 died after a mean survival of 10.2 months (range, 2-51 mo) and 5 are alive a mean of 34.4 months since their operation. There were no instrumentation failures, and alignment was maintained in all patients. The authors emphasize that the necessity for instrumentation and the type of instrumentation employed depends on the extent and location of bony destruction. Correct patient selection for operative therapy and the appropriate application of anterior or posterior instrumentation are essential for optimizing results.