The question arises whether, on the basis of our studies, the laminar flow system and aspiration suit should be considered as useful and effective components of the overall proctocol to prevent postoperative surgical infections. Our observations do not permit a definitive answer. This would obviously depend on the demonstration of a reduction of the incidence of postoperative infection by means of a large controlled study. The infection rate encountered in this study can not be used to draw any conclusion as to the efficacy of the laminar flow systems, since there are too many uncontrollable variables which may be influential in causing a post operative wound infection. Published reports and present data seem to indicate that the airborne route of transmission is of little significance in modern surgery and that the amount of wound contamination is not necessarily a reflection of airborne contamination. Thus, the use of the laminar air flow system and aspiration suits, which are clearly designed to prevent wound infection by the airborne route, does not seem to be justified on this basis at the present time. On the other hand, the use of laminar air flow system and/or aspiration suit by necessity imposes a strict discipline in those operating rooms, where multiple personnel are routinely involved; i.e., they reduced the number of personnel in contact with patient, reduce the traffic about the surgical patient, etc., which may have significant benefits towards the control of surgical wound infections. This enforced discipline may very well account for the significant decrease in the number of positive intraoperative wound cultures in this study when laminar air flow systems and/or aspiration suits were in use.