The field of hospital hygiene in Germany has undergone some changes in recent years. In addition to the traditional focus on hygiene, epidemiological activities in the field of nosocomial infections have become important for many hospitals. In order to measure these infections, a surveillance system has been established in Germany, which is known under the acronym KISS (Krankenhaus-Infektions-Surveillance-System, system for surveillance of hospital acquired infections). The system is based on the experiences and principles of the American NNIS-system (National Nosocomial Infections Surveillance), but takes into account the local circumstances and possibilities of participating hospitals in Germany. Meanwhile, hospitals can select among 6 KISS modules, which focus on the following topics or areas: intensive care units, neonatology intensive care unit, oncology, surgical patients, patients with venous or urinary catheters, as well as outpatients. KISS data may be used for quality management issues by individual hospitals and for benchmarking between hospitals. The time spent for surveillance in each hospital for one of the modules averages between two and three hours per week. The scientific literature on the subject of surveillance has convincingly shown that this kind of activity is cost-efficient. Cost-effectiveness is likely associated with surveillance activities within the KISS framework, as these activities will have a beneficial effect on nosocomial infection rates in participating hospitals.