We examine the literature of corporate governance to investigate the impact of corporate governance mechanisms on performance improvement of the newly privatized companies. We notice that all researches studying this impact considered only the disciplinary angle of governance and omitted the most important one which is the vision based on a cognitive theory of governance. So, we present limits addressed in the literature to the financial approach of governance and show the necessity to incorporate in our analysis both the disciplinary and the cognitive approach for a complete study of this impact.