At organizations where “management” as a concept represents “a management of an organization, what is meant by internal audit is the audit performed within the scope of management function. Internal audit under the responsibility of organization’s management is the core element in determining the effectiveness of control (internal control) environment established within organization. Internal audit activity covers advisory services apart from common traditional audit works. Internal audit, one of five basic functions of management, has become a fundamental element needed by organizations to sustain their strength and to display sustainable achievement at today’s world with intensified competition and increased risks. It is gaining more and more importance as it has undertaken the role of reinforcing the success, reliability and accountability of upper management at organizations. At many countries, internal audit at both public and private sector management has gained a legal basis. Today, internal audit has become a management discipline, which is performed in accordance with international standards.