Professor of law, Petrograd Polytechnic, 1917. Involved in the Tagantsev affair (resistance to communism among the Petersburg intelligentsia). Fled to Finland, 1921.
Professor of the Russian law faculty in Prague, 1923. Professor of Institut d’Etudes Slaves, Paris, 1928. Lecturer in sociology at Harvard University, 1936.
Professor of sociology at Fordham University, 1940-1957. Editor of the magazine Novyi Zhurnal, 1960.