Conventional thinking teaches that the absence of liability - in particular contractual invalidity - is itself the reason for the restitution of transfers in the South African law of unjustified enrichment. However, this book argues that while the absence of a relationship of indebtedness is a necessary condition for restitution in such cases, it is not a sufficient condition. The book takes as its focus those instances in which the invalidity thesis is strongest, namely, those traditionally classified as instances of the condictio indebiti, the claim to recover undue transfers. It seeks to demonstrate that in all such instances it is necessary for the plaintiff to show not only the absence of his liability to transfer but also a specific reason for restitution, such as mistake, compulsion or incapacity. Furthermore, this book explores the reasons for the rise of unjust factors in South African law, attributing this development in part to the influence of the Roman-Dutch restitutio in integrum, an extraordinary, equitable remedy that has historically operated independently of the established enrichment remedies of the civilian tradition, and which even now remains imperfectly integrated into the substantive law of enrichment. Finally, the book seeks to defend in principled terms the mixed approach to enrichment by transfer (an approach based both on unjust factors and on the absence of a legal ground) which appears to characterise modern South African law. It advocates the rationalisation of the causes of action comprised within the condictio indebiti, many of which are subject to additional historically-determined requirements, in light of this mixed analysis.

The publication of the Restatement Third: Unjust Enrichment and Restitution by the American Law Institute in July 2010 was an event of major importance, not only for the development of the law of unjust enrichment in the US, but also for global scholarship relating to this area of private law. The Restatement First appeared in 1937, and the Restatement Second was abandoned; hence the Restatement Third is the most significant survey of the American law on this topic for over 70 years. Private law has been a comparatively neglected area of study in US law schools for several decades, and this is particularly true of the law of unjust enrichment. However, the appearance of the Restatement Third has prompted a renewal of interest in the subject among US scholars, and it is hoped that the present volume of essays will contribute to this revival, while reflecting on the lessons to be learned from the Restatement by other legal systems. Featuring the work of leading scholars from the UK, Germany, South Africa, Canada, Hong Kong and Australia, the essays undertake critical and comparative analysis of the Restatement, and offer fresh insights into the rules that it articulates.

This comprehensive yet accessible Research Handbook offers an expert guide to the key concepts, principles and debates in the modern law of unjust enrichment and restitution.

General Principles and the Coherence of International Lawprovides a collection of intellectually stimulating contributions from leading international lawyers to the discourse on the role of general principles in international law. Offering a comprehensive analysis of the doctrines, practices, and debates on general principles of law, the volume assesses their role in safeguarding the coherence of the international legal system. This important book addresses the relationship between principles of law and the other sources of international law, explores the interplay between principles of law and domestic and regional legal systems and the role of principles of law with regard to three specific regimes of international law: investment law, human rights law and environmental law.