The Pers Z S was the signals intelligence agency of the German Foreign Office (German: Auswärtiges Amt) before and during World War II. It consisted of two cryptologic sections. Pers Z S was the cryptanalytic section which was called Special Service of Z Branch of the Foreign Office Personnel Department (German: Sonderdienst des Referats Z in der Personalabteilung des Auswärtigen Amtes). Its mission was the solution of foreign diplomatic codes and ciphers. The other section, which was the Cryptography Section was called Personal Z Cipher Service of the Federal Foreign Office (German: Personal Z Chiffrierdienst des Auswärtigen Amtes) (abbr. Pers Z Chi). The latter section was responsible for compilation, distribution and security of Foreign Office codes and ciphers. Both were colloquially known as Pers Z S.[1][2][3][4] Though similar in nature and operation to the OKW/Chi cipher bureau, it was a civilian operation as opposed to the military operation at OKW/Chi and focused primarily on diplomatic communications. According to TICOM interrogators it evinced an extraordinary degree of competence, primarily driven by a consistency of development not found in any other German signals bureau of the period.[5] Pers Z S/Chi was the symbol and the code name of the Chiffrierdienst, i.e. the Cryptanalysis Department of Pers Z S. Although little is known about the organization, in the final analysis, Pers Z S labored at diplomatic cryptanalysis for a regime for which there were no diplomatic solutions.[6]
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