Oak Brook
Market InsightsOak Brook is an affluent village in DuPage County with a small portion in Cook County in Illinois. The population was 7,883 at the 2010 census. A suburb of Chicago, Oak Brook serves as home to the headquarters of several notable companies and organizations including McDonald's, Ace Hardware, Blistex, Federal Signal, CenterPoint Properties, Sanford L.P., TreeHouse Foods, and Lions Clubs International.