INTRODUCTION: The standard surgical treatment of lumbar spinal stenosis (LSS) is a facet preserving laminectomy. New posterior decompression techniques aim to preserve spinal integrity and minimize tissue damage by saving bone and midline structures. The goal of this review is to compare the effectiveness of decompression with laminectomy for the treatment of LSS. METHODS: MEDLINE, EMBASE, Web of Science, CENTRAL, ClinicalTrials.gov, and WHO ICTRP up to June 2014 were searched. We included RCTs comparing conventional facet preserving laminectomy (laminectomy group) with a posterior decompression technique that avoids the removal of posterior midline structures or a technique involving only partial resection of the vertebral arch (decompression group). The diagnosis was symptomatic degenerative LSS. Two reviewers selected and assessed risk of bias. RESULTS: Ten RCTs (4 high quality) with 733 patients were included. Decompression techniques were unilateral laminotomy for bilateral decompression in 3 studies, bilateral laminotomy in 4 studies, and split‐spinous process laminotomy in 4 studies. Functional disability and leg pain were not different between decompression and laminectomy. Perceived recovery favoured bilateral laminotomy (2 RCTs, n=223, OR 5.7, CI 2.6 to 12.7). Postoperative instability was less for bilateral laminotomy (3 RCTs, n=294, OR 0.10, CI 0.02 to 0.55), but not for unilateral laminotomy (3 RCTs, n=166, OR 0.28, CI 0.07 to 1.15). Low back pain severity was lower after bilateral laminotomy (2 RCTs, n=223, MD ‐0.51, CI ‐0.80 to ‐0.23), and after split‐spinous process laminotomy (2 RCTs, n=97, MD ‐1.07, CI ‐2.15 to ‐0.00). DISCUSSION: We found no differences between decompression and laminectomy for functional disability and leg pain. Laminotomy techniques resulted in less iatrogenic instability and all decompression techniques resulted in less postoperative back pain than laminectomy. Long term RESULTS and studies on iatrogenic instability are needed.