From 1992 to 1993 he was MIT's Chair of the Committee for Pure Mathematics, since 2004 Chair of the Undergraduate Mathematics Committee, and since 2005 MacVicar Faculty Fellow.
Von 1992 bis 1993 war er dort Vorsitzender des Komitees für Reine Mathematik, ab 2004 Leiter des Undergraduate Mathematics Committee und ab 2005 MacVicar Faculty Fellow.