In most modern hospitals, no one is allowed to enter the operating theatre without wearing a surgical face mask. The practice of wearing masks is believed to minimize the transmission of oro- and nasopharyngeal bacteria from operating theatre staff to patients' wounds, thereby decreasing the likelihood of postoperative surgical site infections. In this era of cost-restraints, shrinking hospital budgets, and evidence-based medicine, many health care professionals have begun to re-examine traditional infection control practices. Over the past decade, studies challenging the accepted dogma of surgical face mask usage have been published. Masks that function as protective barriers are another emerging issue. Due to a greater awareness of HIV and other blood-borne viruses, masks are taking on a greater role in protecting health care workers from potentially infectious blood and body fluids. The purpose of this review is to evaluate the latest evidence for and against routine use of surgical face masks in the operating theatre.