FIPS Publication 200 is a mandatory federal standard developed by NIST in response to FISMA. To comply with the federal standard, organizations first determine the security category of their information system in accordance with FIPS Publication 199.
According to NIST Special Publication 800-53, Revision 4:
FIPS Publication 200, Minimum Security Requirements for Federal Information and Information Systems, is a mandatory federal standard developed by NIST in response to FISMA. To comply with the federal standard, organizations first determine the security category of their information system in accordance with FIPS Publication 199, Standards for Security Categorization of Federal Information and Information Systems, derive the information system impact level from the security category in accordance with FIPS 200, and then apply the appropriately tailored set of baseline security controls in NIST Special Publication 800-53, Security and Privacy Controls for Federal Information Systems and Organizations.
Organizations have flexibility in applying the baseline security controls in accordance with the guidance provided in Special Publication 800-53. This allows organizations to tailor the relevant security control baseline so that it more closely aligns with their mission and business requirements and environments of operation.
FIPS 200 and NIST Special Publication 800-53, in combination, ensure that appropriate security requirements and security controls are applied to all federal information and information systems. An organizational assessment of risk validates the initial security control selection and determines if additional controls are needed to protect organizational operations (including mission, functions, image, or reputation), organizational assets, individuals, other organizations, or the Nation. The resulting set of security controls establishes a level of security due diligence for the organization.
See FIPS 199 and FIPS 200 for more detail.