[1] His work is focused on the German Democratic Republic[2] and its Ministry for State Security (The Stasi).
[3] Kowalczuk trained initially as a mason,[4] and then worked as a janitor.
[3] Since 1990 Kowalczuk has been a member of the "Independent Historians' League" ("Unabhängige Historiker Verband").
[5] Between 1995 and 1998 he served as an "honorary expert member" on the Commission set up by the German Bundestag to try to resolve some of the open questions left over from the single-party dictatorship that had, till 1990, been the German Democratic Republic.
[3] In 2019, Kowalczuk was appointed by the Federal Ministry of the Interior, Building and Community to serve on the committee that oversaw the preparations for the 30th anniversary of German reunification.