The construction of GSB prosthesis and surgical technique was presented. The prosthesis having no fixed axis enables flexion and extension as well as shifting and rolling. Unlike the other systems GSB implantation does not require vast resection of femoral and tibial condyles. This is very important in case of failure and necessity of removal of the prosthesis--the revision arthroplasty or arthrodesis does not result in great shortening of the extremity. GSB prosthesis was implanted by the authors in 25 knees of 23 patients. The average follow up was 9 months. In all cases results were good, complications were not observed. The authors conclude that GSB prosthesis deserves wider propagation in surgical treatment of advanced destructive changes in the knee, especially in rheumatoid patients.