Introduction

The protection of legitimate expectations is by now firmly rooted in arbitral practice. The purpose of protecting legitimate expectations is to enable the foreign investor to make rational business decisions relying on the representations made by the host State. Legitimate expectations are closely linked to the requirements of stability and predictability. However, not every expectation upon which a business decision is taken is protected by international investment law. The Tribunal in Thunderbird v Mexico, of which Thomas Wälde was a member, devoted considerable attention ...