Introduction: Spondylolisthesis is defined as the forward slippage of a cephalad vertebra on a caudal vertebra. The term spondylolysis is also derived from the Greek word “lysis” (loosening). Spondylolisthesis is now specifically used to describe a bony defect in the pars interarticularis, the portion of the neural arch joining caudal to the confluence of the pedicle and the superior articular process and at the most cephalad part of the lamina and the inferior articular process. Spondylolisthesis can be present with or without lysis. Numerous studies prove that reduction of severe high-grade spondylolisthesis is essential, whereas low grade spondylolisthesis depending on the etiology, can be managed by several methods like direct repair of the pars defect in lysis patients or instrumented posterolateral fusion in situ with or without decompression.Material and Methods: A series of 10(7 Females and 3 males) patients with gr3 &gr4 Spondylolisthesis were selected forthis studywith mean age group of 50.All patients were treated by in situ posterolateral fusion with pedicle screws and rods with local bonegraft and functional outcome was assessed using oswestry scoring index.Results: Patients showed good clinical outcome and significant pain reduction in 90%. Restoration for a pain limited comfortable daily life was achieved early.Conclusion: The pedicle screw and rod system is easy to use and allow for anatomic restoration of the isthmus in isthmic spondylolisthesis or restoring the stability after laminectomy/discectomy in degenerative spondylolisthesis.