The update to Special Publication 800-53A contains significant changes to the 2010 version of the publication in both content and format. The revised version will allow organisations increased flexibility in relation to security control assessments and will improve the current security assessment procedures. There will also be a continuation of the integration of privacy issues into the Joint Task Force publications. It is hoped that the changes to the current security assessment procedures in SP 800-53A should result in significant improvements in the efficiency and cost-effectiveness of control assessments for federal agencies.

NIST Press Release