Describes a computer-assisted surgical system which uses a calibrated robot. The authors consider: total knee replacement surgery; motivation for robotic systems in total knee replacement; system operation; CT scan and preoperative planning; femoral fiducial location; femoral component placement; tibial fiducial location and component placement; fixturing; immobilization of the knee; immobilization of the pelvis and ankle; fiducial identification and registration; landmark pins; center of the femoral head; robot system and calibration; calibration using a telescopic ball-bar. >