We have been preferred to the conservative therapy on the lumbar disc herniation. Recently, patients often hope to return to their works as soon as possible, even if they select operative methods. We have operated on 248 patients of lumbar disc heniation by modified Casper's method using microscopy since 1985. Using microscopy, we can operate safely under well-lighted field. Casper reported that this method has ablemish of taking long period in operation. We shortened the operative time by modifying the operative procedures. So we can finish operation in less than 30 minites. Our postoperative managements are as follows; 1) the patient is permitted only to move on the bed during the first week after opration; 2) the patient is permitted to walk only on a plain floor during the second week; 3) William's exercise is started after 2 weeks postoperatively; and 4) the patient is permitted to leave the hospital after 3 weeks postoperatively.