This book delves into the private law of the European Union, not into European private law in a wider sense. It focuses on the impact EU law has on private law. The main motivation for the author’s study is the firm belief that there is a world of horizontal relations outside, though not independent from, the vertical relations steered by the legal institutions of the Member States and the Union. That world of societal interchange is governed by private initiative and the pursuit of private interests; it has since antiquity been subject to rules designated as private law. At all times, rulers have had to provide their peoples with the legal framework and services needed to enable that network of private relations. In exchange for this service to society and in order to achieve the justice expected, they have tried to instil the rules of private law with basic orientations of the respective polity. A similar trend is clearly perceptible in the European Union, which increasingly competes with Member States in this regard.

It is therefore not sufficient or appropriate to deal in an isolated way with areas of private law that are determined by traditional systematic structures, e.g. the law of obligations, the law of property or tort law. All areas of private law, and even specific issues such as the seller’swarranties for hidden defects of a product or the causal link between human conduct and damage arising in the context of liability, are now progressively regulated by a mix of national law and EU law. The embeddedness of the resulting rules in the constitutional and policy context of the Union tends to be neglected if private law is treated in books based on traditional systematic structures. The policy context of private law is especially complex in the case of the European Union, and it is still subject to changes.

That is why this book does not focus on any special area of private law and is not structured in accordance with traditional concepts such as contract, liability in tort or private international law.