The Neil Armstrong Operations and Checkout Building (O&C) (previously known as the Manned Spacecraft Operations Building) is a historic building on Merritt Island, Florida, United States. The five-story structure is in the Industrial Area of NASA's Kennedy Space Center. Its facilities include the crew quarter dormitories for astronauts, and suit-up preparations prior to their flights. The other facility is a large spacecraft workshop used for manufacturing and checking activities on crewed spacecraft. On January 21, 2000, it was added to the U.S. National Register of Historic Places.