The major themes of financial regulation in the U.S., the EEC, and Japan are discussed in four interwoven, but independent, essays. The central focus is the protection of the financial system by insuring prudential rules against systemic risks, particularly through promoting capital adequacy by international and national agreement and with due consideration to the distinction between the banking and securities business. The work concludes with the assertion that international harmonization of regulation is necessary for the long-run efficiency of financial markets.