Seventy-three involved cerebral palsied patients were reinvestigated 10 or more years after hip and/or knee surgery. The average age was 6.3 years at operation and 18.1 years at retest. The results were evaluated as to motor progress and hip position. While preoperatively none of the patients was independently ambulatory, this was true in 18 cases after surgery. Usually free gait however was insecure (household walking). All patients that had been unable to sit independently before surgery remained strictly wheelchair bound. The results of hip realignment differed according to degree of handicap: In 51 patients with preoperative motor age of 8 months or more 43 hip deformities had been present, that could be improved in 29 items and remained unimproved 14 times, while five new deformities developed. This meant 19 deformed hips in this group of patients. In 22 patients, whose motor age at surgery had been below 8 months, improvement of 30 deformed hips had been possible 25 times, but there were 13 newly developed changes and 5 unimproved, so that 18 hips still were found deformed. There was a marked tendency for a-symmetry after surgery: while the relation of unilateral to bilateral deformities was 21:26 before operation, this changed to 27:5 postoperatively. 15 patients developed scoliosis of more than 25 degree, 11 of them in the group with major handicap (n = 22). Our study stresses the ill prognosis of surgery in mostly handicapped cerebral palsied children.