Pentagon Library

Pentagon Library facility hours as of 3/8/2022

Pentagon Library, located in PLC2: Tuesday through Thursday, 0800 - 1600, and by appointment.

Mark Center Annex: By appointment.

Virtual reference services are available Monday – Friday, 0730-1600 through Ask-A-Librarian.  

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Pentagon Library LogoThe Pentagon Library serves the information needs of offices of the Secretary of Defense, Joint Chiefs of Staff, and Military Departments located at the Pentagon.

The Library traces its history back to 1800, when the War Department Library was established. In 1944, the Secretary of War issued a memorandum setting up the Pentagon Library to serve those working in the new office building. The library collection includes historical documents acquired throughout its long history.

As a business library supporting Department of Defense decision-makers and policy-makers, the print and online collections focus on:

  • Military
  • Law and Legislation
  • Government
  • History
  • International Affairs
  • Management and Leadership

Pentagon Library Hours and Locations

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