In recent literature corporate governance of banks has received a valuable interest from academic researchers and policy makers around the world. It is established that in banks failure or weakness of corporate governance has potential to destabilize the economy of a single country as well as other countries. “Basel Committee on banking regulation and Supervision” (BIS, 2010) highlights the key role of ownership structure in corporate governance of banks. Ownership concentration is a distinguished feature of corporations in many developing countries including Pakistan. When ownership is concentrated it helps to mitigate the conflicting issues of the owners and managers. In such a situation there is another type of conflict between owners with large equity and owners with small equity. In such case it is very important to know who the controlling shareholders are. This study empirically investigates the banks’ ownership structure effects in the wake of post privatization era in Pakistan. Addressing the needs of corporate governance of banks in Pakistan State Bank issued “Handbook of Corporate Governance” in 2003. The guidelines and recommendations provided in this handbook are extracted from the policies proposed by “Basel Committee on Corporate Governance”. The objective of the current study is to explore the impact of ownership concentration on i) performance, ii) risk taking and, iii) credit allocation efficiency using sample of commercial banks in Pakistan over the period 2000-2015. Data on concentration of ownership is collected from unconsolidated annual reports of banks. This study further categorizes large shareholders into i) state ownership, ii) family ownership, ii) institutional ownership, and iv) foreign ownership. The study assesses the impact of types of ownership on i) performance, ii) risk taking and, iii) credit allocation efficiency of sample commercial banks in Pakistan. This study also analyses the impact of managerial equity holdings on performance and risk taking of banks in Pakistan. The current study finds that in Pakistan bank performance increases when ownership is either dispersed (less than 30 percent) or highly concentrated (above 70 percent). However, performance decreases when ownership concentration is at intermediate level (30-75 percent on average). Government owned banks are detrimental to their bank performance while family, institutional and foreign ownership has positive influence on bank performance. Insider ownership has significant positive impact on bank performance when managers hold low or very high stakes in banks equity. When managerial ownership is between 12-40 percent, it has significant negative impact on bank performance. Further, the study finds that concentration of ownership has significant direct impact on bank risk taking in Pakistan. Government, family and institutional ownership increase bank risk taking while foreign ownership decreases bank risk taking. Managerial ownership has significantly direct impact on bank risk taking when managers’ ownership is either low or very high. Managerial ownership between 11-40 percent on average has negative impact on bank risk taking.Bank regulations decrease bank risk taking as ownership concentration increases. However, bank regulations affect bank risk taking by various types of owners, differently. This study also finds that ownership concentration of banks has negative impact on credit growth (public and private sector both). Ownership concentration has negative impact on credit allocation efficiency of banks. Government and foreign ownership of banks tend to invest inefficiently; however, family and institutional ownership of banks tend to allocate bank resources efficiently. The findings of this study conclude that in Pakistan high ownership concentration in banks helps to improve bank performance, enables banks to take more risk and invest in inefficient projects. Banks with majority of government ownership are associated with poor performance, high risk taking and inefficient credit allocation. Domestic ownership which comprises family and institutional ownership increases bank performance, bank risk taking and credit allocation efficiency. Foreign ownership of banks with majority of foreign ownership are associated with increased bank performance, less risk taking, and allocating resources to less efficient projects. The findings of this study highlight the need of policy intervention in order to regulate concentration of ownership in Pakistan’s banking industry. Policy makers are also suggested to take measures to encourage public and private banks to invest on rational investment projects instead of advancing credit to related parties.