Goff & Jones is the leading work on the law of unjust enrichment. The first edition appeared fifty years ago, in 1966, and successive editions have played a major role in establishing the central importance of the subject for private and commercial law. The text is comprehensive in coverage and written by highly respected scholars who analyse and explain the principles governing claims in unjust enrichment, demonstrating how these principles have been applied through detailed discussion of case-law. The book is frequently cited in court and continues to set the agenda for future developments in the field. The new 9th Edition is completely up-to-date and contains detailed discussion of important decisions since the last edition. Many chapters have been rewritten to take account of significant new cases, and their impact on topics including the valuation of enrichments, the recovery of benefits from remote recipients, the recovery of benefits transferred by mistake, the recovery of money paid as tax that is not due, and the content of the tracing rules and their significance for the award of proprietary remedies. The 9th Edition of Goff & Jones: The Law of Unjust Enrichment deals with the following six key matters in relation to making a claim: * Explains how a claim in unjust enrichment can be precluded where a defendant's enrichment is mandated by a statute, judgment, natural obligation, or contract * Analyses the principles governing the identification and valuation of enrichment, and explains how these apply to claims for different types of benefit * Considers the requirement that a defendant's gain has been acquired at the claimant's expense * Discusses the different grounds for restitution: lack of consent and want of authority; mistake; duress; undue influence and unconscionable bargains; failure of basis; free acceptance; necessity; secondary liability; ultra vires receipts and payments by public bodies; etc * Examines defences including change of position; ministerial receipt; bona fide purchase; estoppel; counter-restitution impossible; passing on; limitation; legal incapacity; illegality * Explicates in detail personal and proprietary remedies for unjust enrichment