Cipher Bureau
# Cipher Bureau

Cipher Bureau may refer to:

* Cipher Bureau (United States), aka Black Chamber (1919–1929), the US government's first peacetime cryptanalytic organization
* Cipher Bureau (Poland) (Biuro Szyfrów), the interwar Polish unit charged with signals intelligence, cryptography and cryptanalysis that broke the German cipher machine Enigma
* Cipher Bureau (film), a 1938 American film
