The Australian Taxation Office (ATO) is the Commonwealth's principal revenue collection agency. In 1998-99, the ATO accounted for total tax revenue of $135.3 billion. The objective of this audit was to review the ATO's administration of penalties, with particular emphasis on its corporate governance framework and issues relating to consistency, effectiveness and accountability of penalty administration. In particular, the audit examined the administration of two penalty types, Late Lodgement and Tax Shortfall, as case studies.