The Classical economist of the 19th century, with his faith in the ultimate efficiency and equity of free, impersonal markets, would certainly be amazed and dismayed by the developments in foreign exchange markets during the last thirty-five years. With the exception of the United States no important trading nation in the world of today maintains a freely convertible currency. On the contrary, each nation maintains a more or less comprehensive system of controls over the receipts and payments which can be effected in international markets. Recent efforts to reduce the extent and rigor of exchange regu lation, notably in Western Europe, have yielded modest results; it seems unlikely, however, that foreign exchange transactions will ever again be completely free of controL Foreign exchange control, with a greater or lesser degree of bilateralism, is a product born largely of necessity. Two world wars and a major world-wide depression so distorted the pattern of world trade and investment that free markets were simply unable to achieve their normal automatic adjustment. Ex change control, on the other hand, has demonstrated its efficiency as a means of maintaining a semblance of order in disorganized international markets. Unfortunately, however, exchange con trol also has great possibilities for further distortion of the pat tern of world trade, for discrimination, and for economic ex ploitation - for economic effects generally considered undesirable.