In a prospective study, 412 primary and 69 reoperations for herniated lumbar disc were observed and intra- and postoperative complications compiled. Only surgeons with the experience of more than 100 surgical procedures on lumbar discs entered this study. The complication rates of the micro- and macrosurgical techniques are compared. Intraoperative complications range from 7.8% in the microdiskectomies and 13.7% in the macrodiskectomies to 27.5% in the reoperations. Postoperative complications range from 1.4% in reoperation, 3.9% in the microdiskectomies up to 4.2% in the macrodiskectomies. The risk of complications correlates with the age of the patient and the operating time