This study investigates European Union countries’ differences and similarities referring to corporate governance treated as (1) an external tool to overcome the conflict of interest described by the agency theory, and as (2) a result of an institutional environment. We conduct a cluster analysis and uncover an increased cross-country heterogeneity. Our findings might be of interest to European capital market investors. Differentiating between low-level corporate governance countries and high-level corporate governance countries may also be of regulators’ interests who should search for other means to improve country-level corporate governance practices.