Internal audit is central to a company's internal controls system and corporate governance.  In an effort to improve the quality of internal audit and to ensure that internal auditing departments are capable of achieving the rules governing internal audit practices and defined internal audit operational standards, the Code provides that internal audit supervisors shall formulate and maintain a set of "Quality Assurance and Improvement Program" and that an external assessment on the quality of internal audit practices must be conducted at least once every 5 years. 

During June and July 2009, CHT engaged the Institute of Internal Auditors, ROC (Taiwan) (IIA, Taiwan) to conduct an external assessment of its internal audit system.  At the invitation of IIA Taiwan, Lewis E. Burnham, a senior quality assessment expert of the Institute of Internal Auditors directed the global project team for the internal audit assessment and partnered with several senior internal audit supervisors of IIA, Taiwan to form the assessment team.  It took CHT over a month to prepare the information and to submit written responses required for the assessment. The assessment team then conducted a 2-week field audit and interviews with the relevant staff. As a result, CHT was rated the highest in terms of its internal audit department's compliance with general principles and professional ethics.