Preservation commissions, government entities, and non-profit organizations in twenty-seven Illinois communities and counties have conducted property-by-property surveys with the support of federal grants administered by the state. Many of those surveys have provided documentation for future National Register and local landmark listings. Six communities-Blue Island, Riverside, Rock Island, Moline, Nauvoo, and Evanston-have finished building-by-building surveys with grant assistance through the preservation office. The City of Chicago's survey program to record basic information on every building in the city limits is almost complete after nine years. The survey's most useful products are accurate maps of all standing buildings with an assessment of their integrity, photographs, and in-depth histories of the most important buildings.