He is professor of history, humanities university professor and director of the International Center for Advanced Studies at the University of New York. He has written and compiled a large number of books, among which are The Unfinished City and New York Intellect. In 1975 he won the Frederick Jackson Turner Award Toward an Urban Vision, and throughout his career he has received the Getty, Rockefeller and Guggenheim fellowships. Between 2002 and 2003 he was a member of Cullman Center for Scholars and Writers of the New York Public Library, where he still lives today