What have we learned about preventing surgical site infection since 1867 when Lister first prevented surgical site suppuration and septicemia by using carbolic acid to wash wounds, soak dressings, and spray operating room air? In an experiment that laid the foundation for modern surgery,1 9 of Lister’s 11 compound fracture patients healed without amputation or mortality typical of that era. Do we know today which of Lister’s precautions was effective? Carbolic acid was soon replaced with less irritating aseptic technique. More recently, gentler topical antimicrobials with sustained delivery like mupirocin, cadexomer iodine, or ionic silver have been added to the antimicrobial armamentarium. Today, it is surprising how little we know regarding effective usage parameters of antimicrobial agents in preventing surgical site infections (SSI) or their benefits and drawbacks. A Cochrane review,2 discussed in the April 2008 Evidence Corner, found some evidence that cadexomer iodine improved venous ulcer healing, but concluded that further research would be needed to make a definitive conclusion. Antimicrobial agents still require more evidence for optimally safe, effective usage in surgical wound care. The two recent articles featured in this Evidence Corner give us a surprising view of surgical drape safety and efficacy and offer tentative hypotheses regarding steps to prevent SSI with methicillin-resistant Staphylococcus aureus (MRSA).