 The firm was originally headquartered in the Empire Building at 71 Broadway in New York City and maintained another main office in Chicago.By the end of World War I, Shearson Hammill had six branch offices and seven correspondents.In the 1960s Shearson, Hammill became well known for its commercials that suggested "If You Want To Know What’s Going On On Wall Street, Ask Shearson Hammill".