S. A. OŜga aims to provide a concise outline of the theory behind the rate of exchange and the terms of trade, in textbook fashion at an elementary level. The terms of trade are defined as the ratio of the money prices of imports and exports, while the balance of trade is the ratio of the value of exports to imports. The analysis in the book, as pointed out by the author, is limited in several ways. First, it does not go beyond defining and exploring relations between limited concepts, and does not touch upon ways of testing or proving any concepts. Secondly, the book deals with only the theory of ratios of exchange as they pertain to international trade. Yet, the discussion in the book is quite focused, which makes it easy to follow.