Archivo: Are your drawers closed? Manhattan Project security poster

Description: A security poster used in the secret US Manhattan Project during World War 2, whose purpose was to build an atomic bomb. It warned employees to keep drawers in offices closed and put classified documents into locked safes when they were not being used, to prevent unauthorized personnel from seeing them.
Title: Are your drawers closed? Manhattan Project security poster
Credit: Retrieved October 10, 2014 from Leslie R. Groves, Ed. (~1948) Manhattan District History, Manhattan Project, U.S. Army Corps of Engineers, Book IV: Pile Project, Vol. 6: Operations, Appendix B, C, D & E, p. 109, declassified version, on Internet Archive
Author: Unknown: There is a signature in the bottom left of the image that may be "Don L"
Usage Terms: Public domain
License: Public domain
Attribution Required?: No