The past year has again confirmed The Investment Treaty Arbitration Review's contribution to its field. The biggest challenge for practitioners and clients over the past year has been to keep up with the flow of new developments and jurisprudence in the field. There was a significant increase in the number of investment treaty arbitrations registered in the first years of this decade. These cases have come or are now coming to their conclusions. The result today is more and more awards and decisions being published, making it hard for practitioners to keep up.

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 The relentless rate of change in the field rapidly leaves them out of date.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, therefore, 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 fourth 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.

Barton Legum
April 2019