The Yellow Book provides standards and guidance for auditors and audit organizations, outlining the requirements for audit reports, professional qualifications for auditors, and audit organization quality control. Auditors of federal, state, and local government programs use these standards to perform their audits and produce their reports.
The 2018 revision of the Yellow Book is effective for financial audits, attestation engagements, and reviews of financial statements for periods ending on or after June 30, 2020, and for performance audits beginning on or after July 1, 2019. Early implementation is not permitted.
Yellow Book revisions undergo an extensive, deliberative process, including public comments and input from the Comptroller General's Advisory Council on Government Auditing Standards. GAO considered all comments and input in finalizing revisions to the standards.