The focus of the paper is to examine the extent and nature of the process of consolidation in Polish Banking Sector and its impact on efficiency and competition. The paper is organised into the following sections. After the introduction, the second section deals with the social role of the banks. Section three briefly sets out the theoretical underpinnings of the banking consolidation process. It also spells out the motives and factors driving mergers and acquisitions (M&As) and the various methods of consolidation. Trends in M&A activity and the progress in banking consolidation in Poland are detailed in next section. The impact of the consolidation process on competition in the Polish banking sector and efficiency of the merged entities is analysed in section five. The final section briefly sets out the conclusions.