What are NIST 800-53 Control Families?

The NIST 800-53 control families refer to the National Institute of Standards and Technology (NIST) Special Publication 800-53 entitled “Recommended Security Controls for Federal Information Systems.” It is a set of guidelines for federal agencies to follow to maintain the highest IT security and data integrity levels. NIST 800-53 controls are referenced by NIST 800-171 for safeguarding CUI.