The Art Institute of Chicago leverages several custom 4D applications in everyday operations and management. The main client/server database, CITI, hosts data on the entire museum art collection. In a mixed Mac and Windows environment, up to one hundred users – including curators, registrars, conservators, librarians, imaging professionals, administrative and public relations personnel and visitor services – use CITI on a daily basis. 4D allows in-house developers to support the various needs of these individual departments and to quickly respond to their requests. 4D is also used as a web services host to the online collection website, as a source of XML data for the Pathfinder interactive floor plan, for on-location educational games, as a mirrored backup server to the production environment, and as a training server for new employees.