Read into
The process of being read into a compartmented program generally entails being approved for access to particularly sensitive and restricted information about a classified program, receiving a briefing about the program, and formally acknowledging the briefing, usually by signing a non-disclosure agreement describing restrictions on the handling and use of information concerning the program. Officials with the required security clearance and a need to know may be read into a covert operation or clandestine operation they will be working on. For codeword–classified programs, an official would not be aware a program existed with that codeword until being read in, because the codewords themselves are classified.
