Most faculty hold joint appointments with the Woodrow Wilson School and one of four social science departments at Princeton University: Economics, Politics, Psychology, and Sociology. Some faculty hold joint appointments in science departments and research programs sponsored by the University. First and foremost, they are highly accomplished scholars who conduct leading social science research and provide governmental policymakers, politicians, nonprofit organizations, and research centers with expert policy analysis. Recently, faculty were appointed to serve with the Princeton University Provost's Office, the Office of the Vice President of the United States, the Federal Reserve Board, the United Nations, the National Intelligence Council, the President’s Council of Economic Advisors, and the U.S. Department of State, along with numerous think tank and research organizations. Their commitment to the School and society as a whole mirrors the University motto, "Princeton in the Nation's Service and in the Service of All Nations." The 200 graduate students who comprise the entire student body build a remarkably close relationship with over 80 School faculty and approximately 40 visiting lecturers and practitioners. Most elective classes enroll between six and 15 students, which creates a highly participatory and engaging learning environment. The accessibility of faculty is one of the School's most acclaimed characteristics, especially among students who attended large research universities for their undergraduate education.