INTRODUCTION

Until recently one could say with some confidence that acceptance of a general principle against unjustified enrichment was one of the hallmarks of a Civilian system of law. The emergence in Common Law systems of “unjust enrichment” as an important head within the law of obligations has qualified but not altogether eliminated the truth of the observation. Certainly one can still be sure that unjustified enrichment in mixed legal systems is an indicator of the Civilian rather than the Common Law dimension in their development, and that the current state of enrichment law in such systems is a bench-mark against which to test the strength or otherwise of that element in the modern mix. But one should not fall into the error of thinking that unjustified enrichment questions are approached in the same way in all Civilian systems. In a classic article published in the Tulane Law Review in 1962, the late Barry Nicholas distinguished between contemporary French and German approaches, noting that under the former the Code recognised only specific obligations to reverse enrichment in certain defined situations, while the BGB took the general principle as its starting point and developed a regime around that single concept. Although in France jurisprudence and doctrine had developed a general enrichment principle, its extra-codal character meant that it performed only a limited, gap-filling or subsidiary role; whereas in Germany there were no such limits, and the relationship between enrichment and other branches of the law was a matter for substantive and doctrinal analysis of their respective domains.