NIST Special Publication 800-171

The purpose of this publication is to provide federal agencies with recommended security requirements for protecting the confidentiality of CUI: (1) when the CUI is resident in a nonfederal system and organization; (2) when the nonfederal organization is not collecting or maintaining information on behalf of a federal agency or using or operating a system on behalf of an agency; and (3) where there are no specific safeguarding requirements for protecting the confidentiality of CUI prescribed by the authorizing law, regulation, or governmentwide policy for the CUI category listed in the CUI Registry.

The protection of Controlled Unclassified Information (CUI) is of paramount importance to federal agencies and can directly impact the ability of the Federal Government to successfully conduct its essential missions and functions. This publication provides federal agencies with recommended security requirements for protecting the confidentiality of CUI when the information is resident in nonfederal systems and organizations. The requirements apply to components of nonfederal systems that process, store, or transmit CUI or that provide protection for such components. The security requirements are intended for use by federal agencies in contractual vehicles or other agreements established between those agencies and nonfederal organizations.