In recent years there has been growing interest in the law of restitution, with many new books and articles and a number of important decisions in the courts. However, there remains great controversy and some confusion, partly for historical reasons and partly as a result of continuing differences over the relation of the law of restitution to other areas of law, including contract and property law. In this work, the author advances a view of the framework of fundamental principles underlying the law of restitution which offers a means of understanding the tangle of conflicting authorities, and then proceeds to examine the case law in the light of it. As part of his analysis, Jaffey suggests new approaches to understanding the areas of overlap between restitution, contract, trusts and property law.