After World War II (1939–1945), Chicago became an important business center. Many of the buildings constructed in Chicago after the war were offices. Large companies such as Prudential Insurance and Standard Oil wanted their own skyscrapers. In the late 1960s, Sears, Roebuck and Company joined that trend. At the time, Sears was the world’s largest company selling products to people. Its department stores and catalogs offered everything from socks to refrigerators. The company had a large group of buildings on Chicago’s West Side. But the company wanted to move its headquarters into downtown Chicago. In 1968 Sears bought an entire city block on the western edge of downtown. Stores, warehouses, and even part of a street were torn down to clear the way for the tower.