Failed back surgery syndrome (FBSS) is many a times an intractable problem confronted in patients with surgical disease of lumbar spine and at the same time is a pressing problem for the physicians as well. This clinical entity is defined as continuation of pain in the lumbar region and lower extremities following surgery of the lumbar spine. Knowledge of the etiological factors and their prevention is the best line of treatment to overcome the evolution of this syndrome. During this study, which was conducted in Imam Khomeini hospital Tehran from the year 1989 till 1990, 43 out of 114 patients developed "FBSS". 23 cases responded to conservative treatment and psychotherapy whereas medical treatment failed to achieve fruitful results in the rest. The latter underwent extensive radiological investigations and repeat surgery. According to this study, we recommend that in the initial management of these patients. The surgeon should observe the dictum of "5-mis" to overcome and minimize the "FBSS" entity