When surgical gowns first were used, their primary purpose was to protect patients from members of the surgical team. In 1952, it was revealed that although the muslin the garments were made from may have been an effective barrier when dry, it lost barrier capability after it became wet. This disclosure triggered research to develop more satisfactory materials for this unique application. In the interim, the emergence of HIV was accompanied by the need to protect surgical team members from patients, and barrier effectiveness attained even greater importance. During the past 50 years, several attempts have been made to develop a universally acceptable and meaningful test method to demonstrate a material's barrier capability under conditions that simulate usual conditions of use. None has been successful. Today, with the trend toward minimally invasive surgery and pressure to reduce costs, perioperative nurses are confronted with selecting a product that is appropriate for the task and degree of exposure anticipated.