After receiving his PhD in Politics from Harvard, Friedberg joined the Princeton University faculty in 1987 and was appointed professor of politics and international affairs in 1999. He has served as Director of Princeton's Research Program in International Security at the Woodrow Wilson School as well as Acting Director of the Center of International Studies at Princeton. Friedberg is a former fellow at the Smithsonian Institution’s Woodrow Wilson International Center for Scholars, the Norwegian Nobel Institute, and Harvard University’s Center for International Affairs.
In September 2001, Friedberg began a nine-month residential appointment as the first Henry Alfred Kissinger Scholar at the Library of Congress. During his tenure he researched "the rise of Asia and its implications for America." Apart from many articles for Commentary magazine, Friedberg has written several books on foreign relations: In the Shadow of the Garrison State; Strategic Asia 2001-02: Power and Purpose; The Weary Titan: Britain and the Experience of Relative Decline, 1895-1905.
He was one of the signers of the Project for the New American Century documents Statement of Principles (June 3, 1997) and a letter on terrorism submitted to President George W. Bush (September 20, 2001). His name has been connected to the Aspen Strategy Group at the Aspen Institute.
Although Friedberg's international relations philosophy is rooted in concern for the structural organization of power characteristic of the realist school of international relations, he draws from many of the traditions of liberal institutionalism, resulting in what scholar Thomas Christensen has termed a "positive-sum" stance on international relations. Hence, unlike his more pessimistic realist scholars, Friedberg, in a seminal article published in International Security in 1993, advocated continued U.S. engagement in East Asia to serve as a stabilizing force until regional economic integration and multilateral institutions had time to develop. Thus, in contrast to traditional realpolitik scholars, Friedberg believes that conflict is not inevitable in East Asia as China continues to develop as long as multilateral institutions and economic integration are used as tools to manage security dilemmas.