Perhaps the most recognizable legacy of Andrew Carnegie and later, Carnegie Corporation, is the American institution of the free public library. Between 1890 and 1917 Andrew Carnegie and Carnegie Corporation of New York built 2,509 new libraries all over the world, including 1,681 in the Unites States. The recipient communities were required to pass an ordinance, guaranteeing annual tax support fo r the library operations. Later the Corporation moved from brick and mortar to developing librarianship and library science.