 the council on tall buildings and urban habitat (ctbuh) is an international body in the field of tall buildings and sustainable urban design. a not-for-profit organizationbased at the illinois institute of technology in the city of chicago, illinois, united states, the ctbuh announces the title of "the world's tallest building" and is widely considered to be an authority{{cite web |url=http://www.chicagomag.com/radar/deal-estate/december-2011/
1969_establishments_in_Pennsylvania Lehigh_University Organizations_based_in_Chicago,_Illinois Organizations_established_in_1969 Urban_studies_and_planning_organisations