He was a collaborator and adviser to Leonid Brezhnev and Mikhail Gorbachev and, among Soviet politicians, one of those who was the closest to Western Europe.
A personal friend of François Mitterrand, Willy Brandt and Giorgio Napolitano, Zagladin was the theorist of a reformed communism that would be very close to European social democracy.
He graduated from the Moscow State Institute of International Relations and taught there from 1949 to 1956.
He was also Vice-President of the Association for Euro-Atlantic Cooperation (AEAC), which promoted links between Russia and NATO.
He was the deviser of the World Summit of Nobel Peace Laureates, chaired by Gorbachev, and a founder of the Permanent Secretariat of World Summit of Nobel Peace Laureates, the official organizer of the event.