The author in this article seeks to answer the question - whether investors can beat the market by concentrating their portfolios on companies that practice good corporate governance? However, the author has not given conclusive answers. In those countries where the legal system is effective and the level of investor protection is high, good governance should be reflected in the prices of shares. Companies of these countries have already adopted best practice in governance. The scope of corporate governance improving remains marginal. Consequently, it does not translate into a significant change in firms performance and their value. Additional benefits of good corporate governance practices to be found in those countries, where the level of investor protection is weaker (lower effectiveness of formal and informal institutions) and the risk of tunneling and expropriation of minority shareholders is greater.