The American Society of Health-System Pharmacists, the Infectious Diseases Society of America, the Surgical Infection Society, and the Society for Healthcare Epidemiology of America provide practitioners with a standardized approach to the rational, safe and effective use of antimicrobial agents for the prevention of surgical site infections (SSIs). The guideline is based on currently available clinical evidence and emerging issues. I will take this opportunity to briefly remind foot and ankle surgeons of some findings within this 2013 report.1 Clean cases without implants. The guidelines do not recommend antimicrobial prophylaxis for patients undergoing clean orthopedic procedures. These include foot, knee and hand procedures, arthroscopy, and other procedures without instrumentation or implantation of foreign materials. Clean cases with implants (foreign materials). The recommendation is strong for a first generation cephalosporin within 60 minutes of an incision. Clindamycin or vancomycin are appropriate if patients cannot tolerate first-generation cephalosporins. The guidelines recommend re-dosing if the case duration is longer than twice the half-life of the antibiotic. The recommendation for the individual agents, therefore, is four hours for cefazolin and six hours for clindamycin. Vancomycin does not typically require re-dosing. Duration of protection. The most recent data and clinical practice guidelines do not support prophylaxis beyond 24 hours postoperatively. The take home point is that the half-life of the administered preoperative antibiotic should allow antimicrobial activity until skin closure. Prolonged protection with continued antibiotic administration is not beneficial, according to the guidelines. The above recommendations apply to scheduled or planned cases without contamination from trauma or foreign bodies. Open fractures have their own set of published recommendations. There are multiple factors that allow the surgeon to make best decisions for each case, including his or her own hospital guidelines and requirements. The surgeon’s antibiotic regimen of choice should rely on experience and training but one should also consider technique, the duration of the procedure, hospital and operating room environments, instrument sterilization issues, preoperative preparation (e.g., surgical scrub, skin antisepsis, appropriate hair removal), perioperative management (temperature and glycemic control), and the underlying medical condition of the patient. All of these factors may have a strong impact on surgical site infection rates. I recommend reading the entire report for the best available, up to date recommendations and the rationale to support those recommendations. Reference 1. Bratzler DW, Dellinger EP, Olsen KM, et al. Clinical practice guidelines for antimicrobial prophylaxis in surgery. Am J Health-Syst Pharm. 2013; 70(3):195-283.