The recent evolution of banking system, profoundly marked by globalization, has increased the need of a prudential supervision in order to maintain stability and confidence in the financial system. the framework for both internal control system in credit institutions and their internal audit function needed to be revised taking into account all the requirements settled by the Basle Committee on Banking supervision. Therefore, banks' internal control system had to be built on essential elements in order to ensure that the bank will comply with laws and regulations, will achieve long-term profitability, will maintain reliable financial and managerial reporting and will decrease the risk of unexpected losses or damage to the bank's reputation. In addition, the internal audit function, to assure its finality the most effective cooperation between the supervisor, the internal auditor and the external auditor had to be organised
among certain principles.