This volume reviews the nature and scope of informal financial markets in developing countries and elaborates on the theoretical and conceptual models which analyse ‘financial repression’ and other aspects of government intervention in financial markets. It also focuses on the consequences which the prevalence of informal financial markets in developing countries may have for monetary and exchange rate policy. In particular, it attempts to capture the functioning of informal, unregulated markets into macroeconomic models, working towards a general eqUilibrium model with informal financial markets. Two types of informal markets are analysed. The first are for informal lending at terms and conditions which differ greatly from those prevailing in the official banking system. The second are the ‘parallel’ markets for foreign exchange which tend to emerge in response to quantity restrictions on trade and administered allocation of foreign exchange to certain users at official rates, which are well below those on the parellel markets. The key question is whether these informal markets change the efficacy of monetary and credit policy-and, if they do, to what extent and in what direction? Two supporting appendices present econometric analyses of the efficiency of parallel currency markets and the degree of capital mobility in developing countries.