It has been a definitive goal to restore an anterior cruciate ligament insufficient knee to a normal anatomical and physiological joint. There are several surgical methods which can provide the patients with a preinjury activity level. The inidication for specivic treatment must reflect the patients expectation and the potential for their realization. The authors have experienced 18 cases of chronic anterior cruciate insufficient knee treated by Insalls technique at the Orthopedic Department of Sung-Ae Hospital from Jan. 1989 to June 1991. The results were as follows: l. 17 males and one female; the average age was 26.2 years. 2. Pain(17 cases) and giving way sensation(11 cases) were main symptoms. And Lachman test was positive in 94% of the patients. 3. By preoperative KT-1000 arthrometer measurement, the side to side difference at 20 Lbs and maximal force were 6.3mm and 7.7mm and the compliance index was 0.83 on an average. 4. By postoperative KT-1000 arthometer measurement, the side to side difference at 20 Lbs and maximal force were 1.7mm and 1.3mm and the compliance index was 0.08 on an average. 5. Average range of motion of the knee was 0°-140°. And the functional results according to Kennedys criteria were excellent or good in all cases.