JMGT_V2_N3_CS1 Ghazi Louizi Journal on Management 2230 – 715X 2 3 38 55 Banks, governance, board, performance In this study, the importance of the board of directors is shown as internal mechanism of banks governance from its different roles and especially from specificities of governance of these institutes. This importance is also demonstrated in the case of Tunisian banks and the impact of board on their performance is estimated. Empirical validation concerning a panel constructed from 10 Tunisian commercial banks observed over 15 years from 1990 to 2004 watch that size of board, presence of outside and institutional directors and of representatives of the State as well as duality of direction influence positively the performance of these banks that it is market or accounting performance. On the other hand, presence of foreign directors and representatives of public establishments influences negatively this performance. December 2007 - February 2008 Copyright © 2008 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=340