The benefits of spinal surgery for relief of low back and leg pain in patients with degenerative spinal disorders have long been debated. The Spine Patient Outcomes Research Trial (SPORT) was designed to address the need for high-quality, prospectively collected data in support of such interventions. SPORT was intended to provide an evidential basis for spinal surgery in appropriate patients, as well as comparative and cost-effectiveness data. The trial studied the outcomes of the surgical and nonsurgical management of three conditions: intervertebral disk herniation, degenerative spondylolisthesis, and lumbar spinal stenosis. Both surgical and nonsurgical care of intervertebral disk herniation resulted in significant improvement in symptoms of low back and leg pain. Still, the treatment effect of surgery for intervertebral disk herniation was less than that seen in patients who underwent surgical versus nonsurgical treatment of degenerative spondylolisthesis and lumbar spinal stenosis. Across SPORT, more significant degrees of improvement with surgery were noted in chronic conditions of lumbar spinal stenosis and lumbar spinal stenosis with spondylolisthesis. In addition, no catastrophic progressions to neurologic deficit occurred as a result of watchful waiting.