Patients undergoing spine surgeries will have severe perioperative pain which leads to morbidity and demands adequate analgesia. Multimodal analgesia involving NSAIDS, intravenous paracetamol and steroids remains the mainstay for treating the pain in these patients. In spite of the adequate usage of the above drugs most of the patient might require opioids in the immediate postoperative period due to severity of pain. Regional anaesthesia in these cases is administered by giving the local anaesthetic in the epidural space or giving opioids epidurally or intrathecally, though they are rarely practised.  Erector spinae plane (ESP) block described in 2016 as a novel regional anesthetic technique for acute and chronic thoracic pain by Forerro et al ^[1]. It has also been used for postoperative analgesia for breast surgery ^[2] and abdominal surgery ^[3]. With the advances in usage of ultrasound for regional anaesthesia, the performance of plane blocks have become much easier and more reliable. The erector spinae plane block is a myofascial plane block where the local anaesthetics are deposited in the plane between the erector spinae muscle and the transverse process of the vertebrae. The local anaesthetic thereby blocks the dorsal rami of the spinal nerves mainly and also ventral rami. We are studying the efficacy of ultrasound guided ESP block for perioperative analgesia on patients undergoing single level lumbar spine fusion surgery with control group.