Internationally recognized authority on threat assessment in interstate and internal conflicts, with an emphasis on migration, ethnic group relations, and post-Soviet Russia. He is currently the principal investigator of a multiyear international research project on migration and ethnoreligious violence in the Russian Federation funded by the National Science Foundation and the John D. and Catherine T. MacArthur Foundation. His previous projects have been funded by Reuters, NATO, the Kennan Institute for Advanced Russian Studies, the U. S. Institute of Peace, the John W. Kluge Center of the Library of Congress, the National Council for Eurasian and East European Research, the Carnegie Corporation of New York, and the Pacific Basin Research Center at Harvard University. Has published several books, he extensively publishes in academic journals and in the mainstream media.