1. Introduction

Interpretation in philosophy and in law is a venerable topic, older than two millennia. In spite of the arguments exchanged by philosophers and jurists alike during those millennia, not all the issues related to ‘interpretation’ could be settled definitively. In law, from the nineteenth century onwards, and with the advancement of modern civil codes in municipal law of continental Europe, the topic of ‘interpretation’ has received renewed consideration (Koskenniemi 2001). Initially, general rules of interpretation were laid down in the nineteenth century following Roman law ideas. As national laws evolved and diversified, ideas about legal interpretation also evolved, so in the twentieth century legal scholars were able to provide a more nuanced picture of the concept of ‘interpretation’ (Pound 1923; Curtis 1949). Meanwhile, on the international arena, several developments have made even more visible the potential of ‘legal interpretation’ to operate as one of the cornerstones of the international legal system. Thus, after the end of World War II, a complex array of international organisations was created, and numerous treaties were adopted. Later, after the end of the Cold War and with the advancement of a globalised world, characterised by a pluralistic legal order, this picture complicated further as the number of international judicial bodies, and the treaties that they were entrusted with, multiplied apace. It is not surprising then that, in this intellectual milieu, one of the problematic topics of international law, especially in the past two decades, has been whether the multiplication of international judicial bodies leads to the fragmentation of international law. Accordingly, the topic of treaty interpretation has received in the last decade a great deal of attention, especially in relation to the issues of the possible fragmentation of international law that may result from the proliferation of international adjudication fora. Thus, how treaty interpretation is undertaken by international judicial bodies, especially by specialised adjudicatory bodies, is perceived in the scholarship as one of the most salient topics of international law.