Zofia Poznańska, also known as Zosia, Zosha, or Sophia (8 June 1906 – 29 September 1942) was a Polish antifascist and resistance fighter of the Soviet-affiliated espionage group that the German Abwehr intelligence service later called the "Red Orchestra".

[3] After becoming disillusioned with the kibbutz and struggling to reconcile her Socialist-Zionist politics with the displacement of Arab farmers, whose land was being purchased, Poznańska moved to Tel Aviv.

When she returned to Palestine, she found that the Ihud had been suppressed by the British authorities, and she eventually moved to Paris, where she was also active in the communist movement.

[5] In October 1941 Poznańska was sent to Brussels to be a cipher clerk to Soviet GRU intelligence agent and radio operator Mikhail Makarov.

[10] Poznańska committed suicide by hanging on 29 September 1942 in Saint-Gilles prison, Brussels, so that the cipher she was entrusted with would not fall into German hands.