Thirty-three consecutive patients with lumbar spinal stenosis were treated with decompressive surgery aimed at relieving pain. The selection criteria for surgery included marked symptoms and lumbar spinal stenosis demonstrated by myelography. Preoperatively, only 15 patients had claudication; however, 23 experienced relief or exacerbation of symptoms related to changes in posture. A good postoperative result was obtained in 82% of the entire series, but in only 50% of patients whose symptoms were not affected by posture. Of those whose symptoms did have a postural component, a good result was obtained in 96%. The relief of back pain by decompressive surgery was significantly less successful than the relief of leg pain. It is therefore suggested that surgery be restricted to as few levels as possible.