Background: Patients with breast carcinoma treated with Modified Radical Mastectomy (MRM), is associated with appreciable acute postoperative pain and limited shoulder mobility. Postoperative pain is a risk factor in developing chronic Postmastectomy pain. About 40% of women have severe acute postoperative pain after breast cancer surgery, whereas 50% develop chronic postmastectomy pain and have a poor quality of life. Pain following mastectomy was first documented in the 1970s, yet postmastectomy pain syndrome (PMPS) remains poorly defined .Though pain associated with mastectomy is implied, PMPS has also been applied to chronic neuropathic pain following other surgical procedures of the breast, such as lumpectomy in breast-conserving surgery. Regional anesthesia and pain management have experienced advances in recent years, especially with the advent of fascial plane blocks. The erector spinae plane block is one of the newest techniques to be described. In the past two years, publications referring to ESP block have increased significantly. The objective of this review is to give brief overview about ESP block. Ultrasound-guided ESP block could be a choice with better outcome in patients undergoing elective mastectomy as regards lower frequency of hypotension, better efficiency and patient satisfaction