In light of increasing calls for corporate governance of banks and the current financial crisis rooted in failures of governance mechanisms, this paper investigates the structure of the internal control system of banks. I have used a sample of nine leading banks operating in the Italian market to understand the most important characteristics and the mechanisms of integration concerning the internal control system. According to the empirical evidences, various mechanisms and elements of the internal control system were found to contain weaknesses. In particular, the first-level of control appears scarcely structured and lacks a clear definition of roles and responsibilities. Moreover, the mechanisms of organizational and operating integration were developed in only a few cases. Therefore, the Italian banks must promptly focus their attention on strengthening these two areas through tailored actions to ensure the safe and sound management of corporate risks. This paper also suggests to banking industry professionals a framework and some recommendations for the implementation of an effective and integrated internal control system in banks.