Graduate of the Institute of History, University of Warsaw, 1969; PhD and post-doctoral degree (habilitacja) from UW (1976 and 1985 respectively); titular professor since 2003 (UW). Has worked at the Institute of History, University of Warsaw, since 1969 as intern lecturer, assistant lecturer, senior assistant lecturer, assistant professor, senior lecturer; associate professor since 1991. Head of the School of Part-Time Studies at the IH UW 1988-1993; chair of the Advisory Board of the University of Warsaw Archives 1991-1997; Chair of the Advisory Board of the IH UW 1999-2002. Visiting scholar: Piłsudski Institute of America (New York) 1980, Institute for Polish-Jewish Studies in Oxford 1987, University of Alberta 1993; visiting professor: Manitoba University, Winnipeg 1993. Editor at the “Krąg” Independent Publishing House 1982-1984; member of the programme board of Polin. A Journal of Polish-Jewish Studies since 1986; member of the editorial board of the Res Publika monthly 1987-1992, and the Nowa Res Publika monthly 1993-2006; member of the Advisory Board of the Polish Biographical Dictionary since 2005; member of the Council of the Polish History Museum since 2006; member of the Council of the Institute of National Remembrance since 2007.