Robert Endicott Osgood (1921-86) was a United States foreign policy researcher and advisor. He received his Ph.D. from Harvard University and served on the faculties of the University of Chicago (l952-61) and the Johns Hopkins University School for Advanced International Studies (SAIS) from 1962 until 1986. While at SAIS Osgood was Research Associate at the Center of Foreign Policy Research, forerunner of the Foreign Policy Institute which he directed from 1965 to 1973. He was dean of SAIS from 1973 to 1979 and Christian A. Herter Professor of American Foreign Policy until his death.

Osgood also served on the senior staff of the National Security Council under Henry A. Kissinger from 1969 to 1970 and on the State Department's Policy Planning Council from July 1983 to July 1985.

Osgood also taught at the Naval War College, the Salzburg (Austria) Seminar in American Studies, and was the NATO Visiting Professor at the University of Manchester, England. Osgood was a member of the Council on Foreign Relations, the Atlantic Council of the U.S., and the International Institute for Strategic Studies.

Osgood's areas of expertise included U.S. foreign policy, national strategic issues, and the Strategic Defense Initiative (SDI). Among his publications were: Ideals and Self-Interest in American's Foreign Relations (1953), Limited War (1957), NATO: The Entangling Alliance (1962), Force, Order and Justice with Robert W. Tucker (1967), Alliances and American Foreign Policy (1968), Japan and the United States in Asia with George R. Packard III and John Badgley (1968), America and the World, Vol I (From the Truman Doctrine to Vietnam) with Robert W. Tucker (1969), The Weary and the Wary: U.S. and Japanese Security Policies in Transition (1972), America and the World, Vol II (Retreat from Empire?: The First Nixon Administration) with Robert W. Tucker, New Era in Ocean Politics with Ann Hollick (1974), Toward a National Ocean Policy: 1976 and Beyond with Ann Hollick, Charles Pearson, and James Orr (1976), Limited War Revisited (1979), and Containment, Soviet Behavior, and Grand Strategy (1981).