Fazlur Rahman Khan (Bengali: ফজলুর রহমান খান, Fozlur Rôhman Khan) (3 April 1929 – 27 March 1982) was a Bangladeshi structural engineer and architect, who initiated structural systems that form the basis of tall building construction today. Considered the Father of tubular designs for high-rises, Khan became an icon in both architecture and structural engineering. He is the designer of Willis Tower – the tallest building in the United States (and tallest in the world for many years) and John Hancock Centre, a 100-story tall building. He also designed structures that are not high rises such as the Hajj Terminal and helped in initiating the widespread usage of computers for structural engineering. Khan, more than any other individual, ushered in a renaissance in skyscraper construction during the second half of the twentieth century and made it possible for people to live and work in "cities in the sky". Khan in his short life created a legacy of innovations that is without peer and left an unprecedented and lasting influence on the profession, both nationally and internationally. 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. CTBUH named an award after him called Fazlur Khan Lifetime Achievement Medal. Khan's seminal work of developing tall building structural systems are still used today as starting point when considering design options for tall buildings.