Fazlur Rahman Khan (Bengali: Fozlur Rhman Khan) (April 3, 1929 - March 27, 1982) was a Bangladeshi born architect and structural engineer. He is a central figure behind the "Second Chicago School" of architecture,[1] and is regarded as the "Father of tubular design for high-rises".Khan, "more than any other individual, ushered in a renaissance in skyscraper construction during the second half of the twentieth century."[3] He has been called the "Einstein of structural engineering" and the "Greatest Structural Engineer of the 20th Century" for his innovative use of structural systems that remain fundamental to modern skyscraper construction. He is widely known for his work on the John Hancock Center and the Willis Tower (formerly Sears Tower), which was the world's tallest building for several decades.

Source: WIKI