INTRODUCTION

It is commonly acknowledged that during the twentieth century, American and European choice of law have drifted apart: in the United States, the American Conflict of Laws Revolution ousted the traditional vested rights theory and paved the way for a variety of novel approaches focusing on flexibility and fairness in individual cases. In Europe, in contrast, classical choice-of-law theory favoring predictability and legal certainty prevailed. The twentieth century, however, has not only seen transatlantic divergence in choice of law. In fact, after years of vigorous debates, legal regimes on both sides of the Atlantic have adopted the same approach when it comes to the private international law of contracts. Specifically, both American law and European law follow the principle of party autonomy and, therefore, allow parties to choose the applicable law.

Of course, the fact that American law and European law have moved closer over the last few years has not escaped the attention of conflicts scholars around the world. However, up until today the precise extent of transatlantic convergence is essentially unclear. In fact, nobody has, as yet, determined how similar the American and the European concepts of party autonomy actually are. And nobody has, as yet, analyzed how similar the handling of the two concepts is in practice. In this chapter, I will fill this gap by analyzing the design and the practical handling of party autonomy in both Europe and the United States.