Acoustic Kitty was a CIA project launched by the Directorate of Science & Technology in the 1960s attempting to use cats in spy missions, intended to spy on the Kremlin and Soviet embassies, recording the links between the buildings in the area. A battery and a microphone were implanted into a cat and an antenna into its tail. This would allow the cats to innocuously record and transmit sound from their surroundings. Due to problems with distraction, the cat's sense of hunger had to be addressed in another operation. Surgical and training expenses are thought to have amounted to over $25 million.
The first Acoustic Kitty mission was to eavesdrop on two men in a park outside the Soviet compound on Wisconsin Avenue in Washington, D.C. The cat was released nearby, but was hit and killed by a taxi almost immediately. However, this was disputed in 2013 by Robert Wallace, a former Director of the CIA's Office of Technical Service, who said that the project was abandoned due to the difficulty of training the cat to behave as required, and "the equipment was taken out of the cat; the cat was re-sewn for a second time, and lived a long and happy life afterwards". Subsequent tests also failed. Shortly thereafter the project was considered a failure and declared to be a total loss.
The project was cancelled in 1967. A closing memorandum said that the CIA researchers believed that they could train cats to move short distances, but that "the environmental and security factors in using this technique in a real foreign situation force us to conclude that for our (intelligence) purposes, it would not be practical." The project was disclosed in 2001, when some CIA documents were declassified. 
- Charlotte Edwardes (April 11, 2001). "CIA recruited cat to bug Russians". The Telegraph.
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- TV series "The World's Weirdest Weapons", season 1, episode 6: "Weapons Of The Superspies", Yesterday TV
- Jeffrey T. Richelson, The Wizards of Langley: Inside the CIA's Directorate of Science and Technology (Boulder, CO: Westview Press, 2002), 147-48. ISBN 0-8133-4059-4.
- U.S. Central Intelligence Agency (March 1967). "Views on Trained Cats Use". George Washington University. Retrieved March 21, 2014., redacted (pdf)
- Julian Borger (September 11, 2001). "Project: Acoustic Kitty". The Guardian Newspaper.
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