The financial services industry is experiencing rapid consolidation globally. Consolidation has proceeded not only in the same market but also across different market segments and across national boundaries. In this paper, we (a) outline the general trend of the mergers and acquisitions (M&As) and consolidation of the financial service industry in the U.S. and in the global economy; (b) identify and analyze the reasons that contribute to the consolidation of the financial service industry; (c) examine some cases of successful and unsuccessful financial service M&As; and (d) arrive at some strategic implications.