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Professor Zachary Douglas QC has a substantial practice before international courts and tribunals as counsel, arbitrator and expert witness, and also frequently appears before the English courts and the courts of other common law jurisdictions in cases with a public or private international law element. He is a Professor of International Law at the Graduate Institute of International and Development Studies in Geneva and was formerly a member of the Faculty of Law of Cambridge University. Zachary is recognised as a leading specialist in public international law and arbitration by Chambers and Partners and Legal 500 and received the award for International Arbitration at the 2011 Chambers and Partners Bar Awards. He is listed in the Chambers and Partners’ Top 100 UK Bar.

Zachary has been instructed by States in relation to proceedings in the International Court of Justice and the Tribunal for the Law of the Sea. He has acted as counsel in investment treaty arbitrations and commercial arbitrations under the ICC, LCIA, SCC, UNCITRAL, Swiss and ICSID Arbitration Rules and has served as an arbitrator in more than a hundred and thirty cases under the LCIA, ICC, Swiss, UNCITRAL and ICSID Rules, including as chairperson and as sole-arbitrator in more than half of those cases.

Zachary has acted as counsel in cases before the English courts and other municipal courts relating to state immunity, human rights and humanitarian law, state succession, constitutional law, challenges to investment treaty awards, private international law, civil fraud and money laundering. He has represented individuals and companies in proceedings before the European Court of Human Rights. He has also acted in dozens of cases before the Court of Arbitration for Sport, having formerly represented the International Olympic Committee.

In addition to contentious matters, Zachary has advised governments on issues of public international law (law of the sea, treaty law, international human rights, sovereign immunity, humanitarian law, state succession), arbitration legislation and constitutional reform. He has also advised multinational companies on issues of corporate social responsibility and international humanitarian law.

Zachary is fluent in Russian and French and has conducted bilingual arbitration proceedings in both languages. He is the author of one of the leading studies on investment treaty arbitration ‘The International Law of Investment Claims’ published by Cambridge University Press in 2009. Zachary was a Visiting Professor at the Université Panthéon-Assas Paris II in 2013 and a member of the Faculty for the Paris Arbitration Academy in 2014.

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Chambers & Partners 2021 say Zachary is “very organised, gets straight to the point, and is an arbitrator who listens and is truly collaborative.” “One of the best international arbitrators you can get.”

“The hallmark of any good advocate is whether they can cross-examine a witness effectively and his abilities need to be seen to be believed!”

Chambers and Partners Global 2015 and 2016 rank Zachary in Band 1 for Silks in Arbitration (International), Band 1 for Silks in Public International Law (“For international law he’s a one-man library, never mind an encyclopaedia. His knowledge is phenomenal.” “He’s a very good advocate and has a sense of priorities in terms of presenting persuasive arguments on the issues.”) and is one of 16 individuals world-wide listed in Public International Law: Most in Demand Arbitrators (“Standout individual”).

Chambers Top 100 UK Bar says that Zachary “has an exceptional talent for thinking outside the box, and is capable of developing creative and compelling arguments when others might simply have given up without a fight. He is ever the gentleman, is good spirited and is a pleasure to work with.”

Legal 500 2014 says the “phenomenal” Zachary Douglas attracts praise for his “encyclopedic knowledge of international law, particularly around issues of state responsibility”.