The growing worldwide trend towards the formation of financial conglomerates, offering a range of financial services hitherto unprecedented, has caused serious problems for regulators. While conglomeration brings with it many economic benefits in the form of enhanced competition, greater diversification of risk and economies of scope (i.e. 2 + 2 = 5), it also imposes costs; namely the threat of systemic risk and increased conflict of interest abuse. In International Banking Deregulation Richard Dale explores this theme with specific reference to the mixing together of banking and securities business. His study, which is set against a broad canvas of international developments ranging from the Great Crash of 1929 to the recent collapse of Bank of Credit and Commerce International (BCCI), focuses on the prudential, or systemic risk, issues arising from the fusion of banking and securities business—