This year's edition of The Investment Treaty Arbitration Review goes to press under particular circumstances. Measures to contain the covid-19 pandemic around the world have confined authors to quarters. Despite these constraints, the authors of this volume have delivered their chapters. The result is a new edition providing an up-to-date panorama of the field. This is no small feat given the constant flow of new awards, decisions and other developments over the past year.

Many useful treatises on investment treaty arbitration have been written. The relentless rate of change in the field rapidly leaves them out of date.

In this environment of constant change, The Investment Treaty Arbitration Review fulfils an essential function. Updated every year, it provides a current perspective on a quickly evolving topic. Organised by topic rather than by jurisdiction, it allows readers to access rapidly not only the most recent developments on a given subject, but also the debate that led to and the context behind those developments.

This fifth edition adds new topics to the Review, increasing its scope and utility to practitioners. It represents an important achievement in the field of investment treaty arbitration. I thank the contributors for their fine work in developing the content for this volume under the difficult conditions prevailing today.

Barton Legum
Dentons
Paris
May 2020