Unjustified enrichment: surveying the landscape
Preliminary questions ‘Unjustified enrichment’. The expression is mysterious. So are the other terms in use for the same subject, ‘unjust enrichment’ and ‘restitution’. What is an enrichment and when is it unjustified? To state that something amounts to unjustified enrichment is merely a conclusion, that because the enrichment is unjustified it should be returned, restored or made over to the person properly entitled to it. That conclusion is in need of supporting normative argument. But what sort of argument? Some time ago the Roman jurist Pomponius wrote the now-famous words nam hoc natura aequum est neminem cum alterius detrimento et iniuria fieri locupletiorem , ‘by the law of nature it is right that nobody should be unjustly enriched at another's expense’. Pomponius's maxim encapsulates the key elements of enrichment liability: enrichment, which is unjust, and which is at the expense of the claimant. But it exemplifies a problem that faces modern legal systems, too: formulating the principles of a law of unjustified enrichment in a way which is clear and yet not excessively broad. There is no doubt that Pomponius's formulation is, as a matter of classical Roman law, much too broad. There were many cases in which unjustified enrichment was simply allowed to rest where it arose. A clear instance is the claim of a possessor in good faith who improved land from which he was later ejected by the true owner.
A Historical Introduction to the Law of Obligations
1 PROLOGUE: THE PREHISTORY OF THE ENGLISH LAW OF OBLIGATIONS 2 STRUCTURAL FOUNDATIONS 3 UNITY AND FRAGMENTATION OF THE MEDIAEVAL LAW OF CONTRACT 4 TRESPASS, TRESPASS ON THE CASE, AND THE MEDIAEVAL LAW OF TORT 5 THE SUBSTANTIVE LAW OF TORTS 6 THE SUBSTANTIVE LAW OF CONTRACT PART 2 THE TRIUMPH OF TRESPASS ON THE CASE 7 TORT, PROPERTY, AND REPUTATION: THE EXPANSION OF THE ACTION ON THE CASE 8 THE RISE OF THE ACTION OF ASSUMPSIT PART 3 THE MODERN LAW OF TORT AND CONTRACT 9 TRESPASS, CASE, AND THE MORAL BASIS OF LIABILITY 10 THE LAW OF TORTS IN THE NINETEENTH CENTURY: THE RISE OF THE TORT OF NEGLIGENCE 11 THE LAW OF TORTS IN THE TWENTIETH CENTURY: EXPANSION AND COLLAPSE OF THE TORT OF NEGLIGENCE 12 FOUNDATIONS OF THE MODERN LAW OF CONTRACT 13 THE RISE OF THE WILL THEORY THE WILL THEORY AND THE CLASSICAL MODEL OF CONTRACT 14 THE DECLINE OF THE WILL THEORY: LEGAL REGULATION AND CONTRACTUAL FAIRNESS PART 4 UNJUST ENRICHMENT 15 UNJUST ENRICHMENT 16 LEGAL CHANGE AND LEGAL CONTINUITY
The Area of Freedom, Security and Justice ten years on: Successes and future challenges under the Stockholm Programme. CEPS Paperbacks. June 2010
This book celebrates the tenth anniversary of the Area of Freedom, Security and Justice (AFSJ) by bringing together the views of key practitioners and policy-makers who have played an outstanding role in thinking about and shaping EU policies on freedom, security and justice. 
 
Ten years ago, the member states transferred competences to the EU for law and policy-making in the fields of immigration, asylum and border controls, and began the transfer process for criminal justice and policing. This decade of European cooperation on AFSJ policies has experienced very dynamic convergence, the enactment of a large body of European law and the setting-up of numerous EU agencies working in these domains. Such dynamism in policy-making has not been without challenges and vulnerabilities, however. As this collective volume shows, the main dilemmas that lie ahead relate to an effective (while more plural) institutional framework under the Treaty of Lisbon, stronger judicial scrutiny through a greater role for national courts and the Court of Justice in Luxembourg, better mechanisms for evaluating and monitoring the implementation of EU AFSJ law and a more solid fundamental rights strategy. The contributions in this volume address the progress achieved so far in these policy areas, identify the challenges for future European cooperation in the AFSJ and put forward possible paths for making more progress in the next generation of the EU’s AFSJ.