This Report has been prepared by the Aggressive Tax Planning Steering Group of Working Party No. 10 on Exchange of Information and Tax Compliance of the Committee on Fiscal Affairs (CFA). The CFA adopted the Report on 3 January 2011 and agreed to derestrict it. The Report outlines the importance of timely, targeted and comprehensive information to counter aggressive tax planning, provides an overview of disclosure initiatives introduced in certain OECD countries, discusses their experiences with the usefulness of such initiatives (for both taxpayers and tax administrations), and contains a number of conclusions and recommendations. The Report does not deal with tax evasion and the disclosure initiatives discussed in this Report will generally have little or no impact in tax evasion cases.