He has been a Visiting Scholar at Center for Strategic and International Studies, Georgetown University, Washington, D.C., Center for International Affairs, Harvard University, and Institute of International Relations, the University of British Columbia. He has written articles and books on arms control, Soviet and American nuclear policies, Danish and Norwegian security policy, global environmental protection as a Collective Good, and European issues. His major work is the dissertation “American Perceptions of the Soviet Union as a Nuclear Adversary. From Kennedy to Bush”, London and New York: Pinter Publishers, 1989 (published under the auspices of Center for International Affairs, Harvard University). He has been a member of Nordic Cooperation Committee for International Relations, incl. Peace and Conflict Research (NORDSAM), and the Danish Security and Disarmament Commission (SNU). He has contributed to two major studies: Denmark and the Cold War (2005 – in Danish) and “Phasing out the Colonial Status of Greenland 1945-54” (2010 - in Danish 2007). Also, he has attended conferences in “International Institute for Strategic Studies” (IISS), and conventions in “International Studies Association” (ISA).