The Boeing International Headquarters (colloquially known as the Boeing Building and formerly known as the Morton International Building) is a 36-floor skyscraper located in the Near West Side of Chicago. The building has been made the corporate headquarters for Boeing, which decided in 2001 to move from Seattle to Chicago. 100 North Riverside Plaza is poised on the west side of the Chicago River directly across from the downtown Loop. The building responds to the clearance requirements of the site's commuter rail lines with a structural system that uses steel trusses to support its suspended southwest corner. It won the Structural Engineers Association of Illinois' "Most Innovative" Design Award. The building was originally constructed for the Morton Salt Company, and has also housed offices of Ameritech.