Dead drop

For a USB device used as a public dead drop, see USB dead drop.
This (replacement) mailbox is identical to the one, and in the same location that convicted spy Aldrich Ames used to signal his Russian counterparts. Ames would place a horizontal chalk mark about 3" long above the USPS logo.

A dead drop or dead letter box is a method of espionage tradecraft used to pass items or information between two individuals (e.g., a case officer and an agent, or two agents) using a secret location. By avoiding direct meetings, individuals can maintain operational security. This method stands in contrast to the live drop, so-called because two persons meet to exchange items or information.

Spies and their handlers have been known to perform dead drops using various techniques to hide items (such as money, secrets or instructions) and to signal that the drop has been made. Although the signal and location by necessity must be agreed upon in advance, the signal may or may not be located close to the dead drop itself. The operatives may not necessarily know one another or ever meet.[1][2]

  1. ^ Robert Wallace and H. Keith Melton, with Henry R. Schlesinger, Spycraft: The Secret History of the CIA's Spytechs, from Communism to al-Qaeda, New York, Dutton, 2008. ISBN 0-525-94980-1. Pp. 43-44, 63, and 74-76.
  2. ^ Jack Barth, International Spy Museum Handbook of Practical Spying, Washington DC, National Geographic, 2004. ISBN 978-0-7922-6795-9. Pp. 119-125.