Epidemiological findings of a single outbreak event may not be generalized; however, the characteristics of a typical outbreak can be determined on the basis of a large number of similar events. The Outbreak Database ( http://www.outbreak-database.com ) is the largest collection of nosocomial outbreaks currently available-and is still expanding. Articles are filed systematically, enabling those on a specific parameter of interest to be retrieved quickly. As such, this database is an extremely valuable tool on many medically related fronts, such as for educating other medical personnel, providing relevant information during the investigation of an acute outbreak, or addressing scientific-oriented questions. Several systematic reviews on a wide range of subjects, including sources of infections, types of pathogens, routes of transmission, appropriate infection control measures, and patients at risk of infection, have already been published based on information contained in this database. As this database may be used free of charge, all medical staff in the field of infection control, hygiene, and hospital epidemiology should be aware of its existence.