He has lectured at over 300 colleges and universities in the United States and abroad and held visiting positions at over a dozen, including Fulbright lectureships in Israel and India, and the Pitt Professorship of American History and Institutions at Cambridge University.
ATP International Series | International Monetary Fund | New York Stock Exchange | International Red Cross and Red Crescent Movement | ATP International Series Gold | International Space Station | Amnesty International | Second Vatican Council | International Olympic Committee | World Boxing Council | United States National Research Council | BirdLife International | National Research Council | International Finance Corporation | International Organization for Standardization | International Telecommunication Union | International Criminal Court | Privy Council of the United Kingdom | One Day International | International Nonproprietary Name | International Labour Organization | British Council | International Civil Aviation Organization | International Boxing Federation | London Stock Exchange | Toronto International Film Festival | International Atomic Energy Agency | International Maritime Organization | International Development Association | John F. Kennedy International Airport |
In addition to his committee work at Chicago and Yale, McClellan served on the Board of the Council for International Exchange of Scholars (CIES), the American Advisory Committee of the Japan Foundation, the American Oriental Society, the National Endowment for the Humanities (NEH), the editorial board of the Journal of Japanese Studies, and visiting committees in East Asian studies at Harvard and Princeton.