Book excerpt: Interest has always been a part of humans' daily economic life, and the concept of interest has attracted intense attention from economists, philosophers, religious scholars and lawmakers. This book analyses the issue of prohibition of interest through the lens of conventional economics and then makes a comparison with the position of Islamic economists. It evaluates the theory of interest presented by Böhm-Bawerk, which is the most respected and applicable theory at present. It provides an in-depth analysis of the current literature, and it is the first book to scrutinize the interpretation of Islamic economists on the concepts of time preference and interest rate control. This book will be of interest to academics and students of economics and Islamic economics.