"Three years have passed since the publication of the fourth edition of this book. During this time, the world of international trade law and policy has changed beyond recognition. In these times of populist anti-globalism, economic nationalism, trade protectionism and superpower geopolitical confrontation, the multilateral trading system and its principal institution, the WTO, are in crisis. The fifth edition of this book has been updated and revised to reflect the developments in WTO law and policy up to 1 August 2020. This edition is, as was the prevous edition, accompanied by an on-line supplement, containing questions, assignments and exercises, which will be regularly updated and may assist students (and practitioners) to further their understanding of WTO law and policy. This book reflects the current state of WTO law. It is not our ambition in this book to express an opinion on how issues not yet adjudicated should be decided or, more broadly, how WTO law should develop in the future. Where we quote or refer to various and often divergent statements of negotiators, academics or other eminent experts, we do so in order to give the reader a full picture of open debates. It is evident that the description of the current state of WTO law contained in this book is to be attributed to the authors in their private capacity and does not represent the views of the organizations to which they belong".