The United States Government has published the National Security Agency (NSA) Commercial National Security Algorithm (CNSA) Suite, which defines cryptographic algorithm policy for national security applications. This document specifies the conventions for using the United States National Security Agency's CNSA Suite algorithms in Secure/Multipurpose Internet Mail Extensions (S/MIME) as specified in RFC 8551 #. It applies to the capabilities, configuration, and operation of all components of US National Security Systems that employ S/MIME messaging. US National Security Systems are described in NIST Special Publication 800-59. It is also appropriate for all other US Government systems that process high-value information. It is made publicly available for use by developers and operators of these and any other system deployments.