First published in 1960, presents an analysis of the determination of interest rates and asset prices with the help of few simple assumptions. The theory can be regarded either as an alternative to the liquidity preference theory or as an extension of it. Like that theory, it is aggregative and simple, but it is applicable not only to interest rates on government securities but also to yields on real assets. Furthermore, it can be formulated in terms of actually measurable variables, so that it is directly applicable to particular situations. This is demonstrated by a statistical example relating to the average yield on U.S. Government securities in the post- war period. In addition to the main analysis the author discusses the role of financial intermediaries and the structure of interest rates, and there is also a re-examination of the determinants of the transactions demand for money. This is book is an essential read for students of economics.