Polski Słownik Biograficzny (PSB; Polish Biographical Dictionary) is a Polish-language biographical dictionary, comprising an alphabetically arranged compilation of authoritative biographies of some 25,000 notable Poles and of foreigners who have been active in Poland – famous as well as less-well-known persons – from Popiel, Piast Kołodziej, and Mieszko I, at the dawn of Polish history, to persons who died in the year 2000. The Dictionary, published incrementally since 1935, is a work in progress. It currently covers entries from A to S and its completion is expected about 2030.