Preface Table of Cases Table of Statutes Table of Statutory Instruments Table of non-UK Statutes Table of Abbreviations PART Ⅰ——INTRODUCTION 1.General Principles 1.Introduction 2.The Principle of Unjust Enrichment 3.The Limits to a Restitutionary Claim based on Another's Unjust Enrichment 4.The Classification of Restitutionary Claims 2.Proprietary Claims and Proprietary Remedies 1.Why Would a Claimant Wish to Vindicate his Proprietary Title? 2.Proprietary Claims 3.Tracing Value at Law and in Equity 3.Subrogation 1.General Principles 2.The Established Categories of Subrogation 3.Authorised Borrowings: The Discharge of the Borrower's Valid Liabilities 4.Unauthorised Borrowings: The Discharge of the Borrow- er's Valid Liabilities PART II——THE RIGHT TO RESTITUTION Section One: Where the Defendant has Acquired a Benefit from or by the Act of the Plaintiff A.Mistake 4.Recovery of Money Paid Under a Mistake of Fact 5.Recovery of Money Paid Under a Mistake of Law 6.Restitution in Respect of Services Rendered Under a Mistake 1.Introduction 2.Restitutionary Claims Arising from Mistaken Improve- ments to Land 3.Other Restitutionary Claims 7.Restitution in Respect of Chattels (Other than Money) Transferred Under a Mistake 8.Recovery of Land Transferred Under a Mistake 9.Relief from Transactions Entered into Under a Mistake 1.Rescission 2.Rectification 3.Reopening Accounts B.Compulsion 10.Recovery of Benefits Conferred Under Duress 1.Introduction 2.The Established Categories of Duress 3.Duress and Submission to Honest Claims 4.Proprietary Claims 5.Failure to Tender Amends 11.Recovery of Benefits Conferred Under Undue Influence 1.General Principles 2.Actual Undue Influence 3.Presumed Undue Influence 4.Limits to Relief and Defences 5.Propriety Claims 12.Relief from Unconscionable Bargains 1.In Equity 2.In Admiralty 13.The Right to Contribution or Recoupment 1.General Introduction 14.The Right to Contribution 1.Introduction 2.Particular Contribution Claims 15.The Right to Recoupment: Compulsory Discharge of Another's Liability 1.The Claimant's Payment must have been Compulsory 2.The Claimant must not have Officiously Exposed himself to the Liability to Make the Payment 3.The Claimant's Payment must have Discharged a Liability of the Defendant …… PART Ⅲ——DEFENCES