The principles ot total joint arthroplasty recently have been expanded to the upper extremity, following the dramatic success with total hip and total knee replacement procedures. New problems have been encountered with the rebalancing of the soft tissues and the technical nature of joint mechanics in the upper extremities. Work on shoulder joint replacement is in the very early stages and of unknown success. Several prostheses are being used and tested. For elbow and wrist replacement, early and predictable success has been accomplished, enabling relief of pain and satisfactory motion. Total joint replacement in the fingers and thumb has provided excellent relief of pain but has been hindered by difficulties in rebalancing the soft tissues in patients with rheumatoid arthritis. It appears that total reconstruction of arthritic upper-extremity joints will be commonplace in the not-too-distant future. Clinical trials are being expanded, with increasing success.