This article analyzes the costs andbenefits of different degrees of competition and differentconfigurations of permissible activities in the financialsector and discusses the related implications for regulationand supervision. Theory and experience demonstrate theimportance of competition for efficiency and confirm that acompetitive environment requires a contestable systemmeaning one that is open to competition-but not necessarilya large number of institutions. A competitive banking systemcan improve the distribution of consumer credit, enhance thecorporate sector's access to financing, and mitigatethe risks of financial crises. In an open market, in whichservices and products are provided in response to marketsignals, financial institutions respond by offering a widerscope of financial services. The optimal institutionaldesign for supervisory functions is less obvious. Thisarticle reviews alternative frameworks for financialservices markets from an economic perspective usingexperiences in several countries as a guide. Authors focusfirst on the role of competition in the financial sector andthe tradeoffs between competition on the one hand andstability and innovation on the other. Authors next examinealternative structures of financial services dictated inmany countries.