A total of 18,249 appendectomies, 32,912 herniorrhaphies, 42,949 cholecystectomies and 19,523 colon operations were analysed. The overall surgical site infection rate was significantly higher (2.6-fold) for the open approach compared to laparoscopically performed appendectomies. For herniorrhaphies, cholecystectomies and colon operations the corresponding odds ratios were 3.40, 3.22 and 1.20 respectively. Whenever possible a laparoscopic approach should be used.