Campbell McLachlan

Campbell McLachlan KC was elected in 2023 to the Professorship of Law (1973) in the University of Cambridge. He is Professor of International Dispute Resolution in the Law Faculty, Fellow of Trinity Hall and Fellow of the Lauterpacht Centre for International Law.

Career

A New Zealander, Campbell was educated at Victoria University of Wellington (LLB (Hons), 1984) and University College London (Ph D, 1988). He holds the Diploma cum laude of The Hague Academy of International Law (1985). After a career in practice in London, where he was a partner in Herbert Smith (1992–2003), and head of its International Law practice group, he returned to New Zealand in 2003 to a chair in law at Victoria University, where he was based until his election at Cambridge (continuing his association with Victoria as Adjunct Professor). He has held visiting positions at All Souls College Oxford; New York University; and as a Senior Research Fellow, in the Berlin-Potsdam research group ‘International rule of law: rise or decline?’ (2019–20). In 2015, he was elected to the Institut de Droit International. In 2022-23, he held the Arthur Goodhart Professorship of Legal Science in the University of Cambridge.

Research

His research focuses on public and private international law and international arbitration. He has been Rapporteur of the ILA Committee on International Civil and Commercial Litigation Committee (1992-2002); Co-Chair of the ILA Study Group on the Practice and Procedure of International Courts and Tribunals (2002-10); President of the Australian & New Zealand Society of International Law (2006-09); and Rapporteur of the 18th Commission of the Institut de Droit International on ‘Equality of Parties before International Investment Tribunals’ (2015-19). He was elected to the American Law Institute in 2005, where he has served as an international adviser on the Restatement 4th Foreign Relations Law.

Major publications

His major books include: International Investment Arbitration: Substantive Principles (with L Shore & M Weiniger) (Oxford UP 2007; 2nd ed., March 2017); Foreign Relations Law (Cambridge UP, 2014); and The Principle of Systemic Integration in International Law (Oxford UP, 2024).

He has delivered two courses at The Hague Academy of International Law, both published in the Recueil des Cours and as pocketbooks: his special course, Lis Pendens in International Litigation (Brill, 2009); and his general course, On the Interface between Public and Private International Law (Brill, August 2025).

He has been a Specialist Editor of Dicey, Morris and Collins on the Conflict of Laws and Joint Editor-in-Chief ICSID Review–Foreign Investment Law Journal since 2012. In 2026, he will become Editor-in-Chief of the Cambridge Law Journal.

Teaching

In 2025-26, Professor McLachlan will teach the following courses:

• Tripos Paper No 48: Conflict of Laws (with Professor Merrett and Dr Varesis)
• LLM Paper No 3: International Dispute Resolution (with Dr Varesis)
• LLM Paper No 44: International Law as a Legal System (with Professors Donoghue and Bartels)

Professor McLachlan supervises Tripos students at Trinity Hall in Conflict of Laws and International Law.

He is accepting applications from PhD students in public and private international law and international dispute resolution.

Practical experience

Professor McLachlan brings to his teaching and research practical experience in international dispute resolution. He was appointed Queen’s (now King’s) Counsel in 2007. He is a Member (on the nomination of New Zealand) of the Permanent Court of Arbitration and of the Panel of Arbitrators at the International Centre for the Settlement of Investment Disputes (ICSID); as well as a Member (on the joint proposal of the UK and the EU) of the Panel of Independent Chairs of Arbitral Tribunals under the UK-EU Cooperation Agreement. He is an Associate Member of Essex Court Chambers (London) and of Bankside Chambers (Auckland & Singapore). He is frequently appointed presiding arbitrator of international arbitral tribunals.

Additional resources

• Entry in the Eminent Scholars Archive
• 'On the Interface between Public and Private International Law' 1973 Professor Inaugural Lecture (6 February 2025)
• 'The legal science of the international' Goodhart Lecture (6 February 2023)