Robert Volterra


“Robert Volterra is the best public international lawyer around”
– Legal 500 2023

“Robert Volterra is probably the best public international lawyer on the planet”

– Chambers and Partners 2022

Robert has been recognised for many years in the global legal directories as one of the world’s top public international law practitioners.  He is qualified as a barrister in Canada and as a solicitor-advocate in England and Wales.  He advises and represents governments, international organisations and private clients on a wide range of contentious and non-contentious public international law and international dispute resolution issues, including international humanitarian law, the laws of war, international criminal law, boundaries and territorial integrity, UNCLOS, international investment agreements and BITs, the Energy Charter Treaty, ICSID, NAFTA, trans-boundary resources and pipelines, joint-development zones and straddling resource regimes, diplomatic and consular law, attribution, privileges and immunities, State responsibility, treaty interpretation and drafting, international arbitration and litigation, international organisations, human rights, resource concessions, Statehood and sanctions.  He regularly acts as co-agent, counsel and advocate before the International Court of Justice and ad hoc international arbitration tribunals, including under the Permanent Court of Arbitration, ICSID, ICC, SCC, LCIA, UNCITRAL, WTO and UNCLOS rules.  He regularly sits as an arbitrator in ICSID, UNCITRAL, ICC, SCC and LCIA arbitrations. He is on the UK Attorney General’s A-list for public international law practitioners.

Robert’s practice focuses on the resolution of complex disputes and evolving issues in the field of public international law.  He is sought by clients globally to defend their interests in bet-the-country and bet-the-company disputes.  He is the go-to public international law practitioner for cases dealing with novel and cutting-edge topics.  His cases are widely referenced in public international law text-books and journal articles; they are cited and relied upon extensively as precedents and guides by domestic and international courts and tribunals.

Robert combines being a seasoned practitioner with being a thought-leader in the field of public international law. He is a Visiting Professor of International Law at University College (UCL), University of London, where he has taught the international law of foreign investment for almost 20 years. He is a Visiting Senior Lecturer at King’s College, University of London, where he has taught the international law of boundary disputes for several decades. He is invited to lecture on a variety of public international law topics in Europe, the Americas, Africa and Asia. He publishes regularly. He is on the International Law Advisory Board of the British Institute of International and Comparative Law. He is on the Management Board of the Investment Treaty Forum. He is a member of the ICC Latin American Arbitration Committee. He is on the Expert Panel for States of UNCTAD’s Programme on Dispute Settlement in International Trade, Investment and IP. He is a Legal Expert on the Energy Charter Secretariat’s Legal Advisory Task Force.

The Legal 500 and the Chambers & Partners legal directories consistently rank Robert in the top tier of practitioners globally.  Over the years, these two directories have recorded that Robert is described by clients and peers as follows: “a fantastic lawyer”; “one of the leading investment arbitration and international law solicitors in the world”; “very smart”; “a tenacious advocate”; “combines commercial and public international law experience”; “a ‘phenomenal lawyer’”; “both an excellent lawyer and an excellent team leader”; “great breadth and depth, with strength in international arbitration, border, treaty, and investor/state disputes”; “a pre-eminent PIL specialist”; “widely acknowledged as a leader in public international law arbitrations”; “highly recommended”; “a star player”; “a leading reputation”; “a thorough and analytical approach”; “a brilliant and open approach”; “excellent ability to communicate legal proceedings to foreign clients”; “a well-known and celebrated practitioner”; “expertise in investment arbitrations as well as traditional PIL matters”; “a venerated figure”; “formidable”; “market leader”; “top-class practitioner”; “a global player”; “a brilliant PIL lawyer – strong and astute”; “well liked as an advocate”.

Direct dial: +44 (0)207 380 3898



LLMi, University of Cambridge, United Kingdom

LLB, Osgoode Hall Law School, York University, Canada

BA, University of Western Ontario, Canada


English, French, Spanish, Italian

Bar admissions

Ontario, England and Wales