Sears conglomerate during the mid-20th century, adding Dean Witter and Coldwell Banker real estate in 1981, starting Prodigy as a joint venture with IBM in 1984, and introducing the Discover credit card in 1985. In 1974, Sears completed the 110-story Sears Tower in Chicago, which became the world's tallest building, a title it took from the former World Trade Center towers in New York. Sears moved to the new Prairie Stone Business Park in Hoffman Estates, Illinois, between 1993 and 1995. The Sears Centre is a 10,001-seat multi-purpose arena located in Hoffman Estates adjacent to the Prairie Stone campus. Even though
Metropolitan Tower (Chicago) White, the Metropolitan Tower was named the Straus Building when completed in 1924. Though it was the first building in Chicago with 30 or more floors, it was never officially designated Chicago's tallest building since the Chicago Temple Building, also completed in 1924, is taller by but has seven fewer floors. The Straus Building and the Chicago Temple Building were the first to take advantage of the 1923 zoning ordinance; before then, no building in Chicago could be taller than . The Metropolitan Tower was at one time called the Continental National Insurance Company Building (later Continental Center I). From