Cross-section comparisons of various towers, from ground level to top: Burj Khalifa, Taipei 101, Willis Tower, and World Trade Center The tower was designed by Skidmore, Owings, and Merrill (SOM), which also designed the Willis Tower (formerly the Sears Tower) in Chicago and the One World Trade Center in New York City. Burj Khalifa uses the bundled tube design of the Willis Tower, invented by Fazl