A posterior decompression with an instrumented fusion is one of the most common surgical procedures performed for treating symptomatic spinal stenosis associated with degenerative spondylolisthesis (DS). However, some patients may benefit from a decompression alone, avoiding complications related to instrumentation and fusion. Objective: To identify the characteristics of patients with symptomatic DS who may be successfully treated with an isolated decompression. Study Design: A systematic literature review of studies including patients who underwent decompression without instrumentation for treatment of DS. Methods: A systematic review of the Medline database was performed. Retrospective and prospective studies of patients with DS who underwent a decompression were included, as well as studies comparing decompression with instrumented decompression. All the articles were classified according to their level of evidence. Results: Thirteen studies met all inclusion and exclusion criteria. We identified several characteristics that may be associated with a less favorable outcome after a decompression alone: a facet angle > 50 degrees, a disk space of > 6.5 mm, presence of low back pain rather than lower extremity symptoms, presence of hypermobility in the listhetic level on dynamic radiographs (> 1.25 to 2 mm), and resection of the posterior elements. The majority of the studies comparing decompression alone to decompression and instrumented fusion included in our review suggested similar clinical outcomes with both procedures; however, with long-term follow-up, fusion may provide better outcomes. Decompression with a noninstrumented fusion is also a good alternative to improve symptoms in selected patients, potentially decreasing the risk of reoperation compared with an instrumented fusion. Conclusions: Satisfactory clinical outcome can be achieved with an isolated decompression in selected patients, avoiding the additional risks and costs of instrumentation and spinal fusion. Noninstrumented fusion is also an interesting alternative to instrumented fusion for well-selected patients to decrease complications related to instrumentation.295191202