Under the Action 13 Minimum Standard of the OECD/G20 BEPS Project, jurisdictions have committed to foster tax transparency by requesting the largest multinational enterprise groups (MNE Groups) to provide the global allocation of their income, taxes and other indicators of the location of economic activity. This unprecedented information on MNE Groups’ operations across the world has boosted tax authorities’ risk assessment capabilities. The Action 13 Minimum Standard was translated into specific terms of reference and a methodology for the peer review process. The peer review of the Action 13 Minimum Standard has completed four annual reviews in 2017, 2018, 2019 and 2020. These cover the three key areas under review: the domestic legal and administrative framework, the exchange of information framework, and the confidentiality and appropriate use of Country-by-Country (CbC) reports. This 2021 annual peer review report reflects the outcome of the fourth review which considered all aspects of implementation. It contains the review of 132 member jurisdictions of the OECD/G20 Inclusive Framework on BEPS which provided legislation or information pertaining to the implementation of CbC Reporting.