The complexity of surveillance, prevention, and control of nosocomial infections has increased over the last decades, owing to reductions in the length of hospital stay, health care practice outside of the hospital (home care, day hospital care, long-term care facilities, nursing homes), the increase in the number of elderly patients, new and emerging diseases, multidrug-resistant pathogens, and the administrative requirements for accreditation. In this setting, infection control nurses are progressively assuming new responsibilities in addition to infection control, such as ensuring the safety of the patient, guaranteeing health care quality, and other tasks. In the light of these changes, professional organizations of infection control personnel have voiced the opinion that staffing for infection control work should not be based solely on the number of hospital beds, but also on the complexity of the tasks involved, which should be defined according to standardized criteria and infection control indicators. In addition, the cost-benefit relationship of infection control programs should be demonstrated.