The challenge posed by healthcare-associated infections is now widely recognized as a public health issue in our country, where the fight against these infections acquired in hospitals has become a top priority for our healthcare system. The human (morbidity, mortality) and economic consequences of these infections have been extensively documented, but it is now essential to raise awareness of this issue among all stakeholders in our hospital system. The prevalence survey of nosocomial infections conducted in 1996 by the Ministry of Labor and Social Affairs highlighted the significance of this health issue. The rate of patients infected with one or more nosocomial infections on a given day was 6.7% of patients present, and the infection rate was 7.6%. As part of the five-year plan, a new prevalence survey was scheduled to be conducted within the next five years. The year 2001 was chosen for this study. Although other procedures for measuring nosocomial infections have been implemented since 1996—notably incidence surveys conducted through the C.CLIN network—the prevalence survey remains, for many institutions, a simple way to assess the extent of this problem. (R.A.)