Introduction

In the last 15 years, a number of books, including one by the present author, and numerous articles have been published on the fair and equitable treatment ('FET') standard. The standard is found in the overwhelming majority of BITs and has become, in the last decades, one of the most controversial provisions examined by arbitral tribunals. According to a 2023 OECD paper, examining 2,670 treaties concluded by 99 jurisdictions, the FET clause is found in 95% of them.

In a recent book, I have examined how tribunals have assessed FET clauses and their relationship with the Minimum Standard of Treatment ('MST'). I have also examined whether their reasoning on that point has had any impact on how they have interpreted the content of the standard and assessed matters of liability and compensation. In the context of this comprehensive empirical research project, I have examined all publicly available awards rendered by arbitral tribunals in the last 25 years dealing with FET clauses. The idea for this book has its origin in a presentation I gave in Paris in 2023 before the Member States of the OECD, and other States invited to the event (99 countries in total). The event was part of the OECD Track 2 program ('Future of Investment Treaties'). A summary of my findings has been published on the OECD website. I have found 279 relevant awards. I have examined awards separately for each of the following three types of FET clauses:

• Clauses containing an unqualified formulation of the FET obligation, i.e., a 'stand-alone' obligation to provide FET without any reference to international law or any other standards (found in 120 awards);
• Clauses containing an explicit reference to the standard existing under 'international law' (found in 63 awards); and
• Clauses where the FET obligation is expressly linked to the MST under custom (found in 42 awards).

Footnotes omitted from this introduction.