1. A retrospective analysis of the postoperative infections and related factors in 1,287 orthopaedic operations has been presented. 2. Postoperative wound infection is a significant problem in the area surveyed, occurring in 4.35 per cent of the cases. 3. The occurrence of postoperative wound infection is determined by many etiological factors, some of which have been described. The particular surgeon, the length of time that the wound is open, and improper use of antibiotics were shown to be significant factors in the incidence of infection.