Nathalie Allen is an experienced international arbitration lawyer specialising in both international commercial arbitration and investor state disputes.  She has been described as an "extremely impressive" arbitration lawyer who is "very bright and experienced".  Peers comment that she has "always shown a quick understanding of legal issues".  Nathalie has frequently been recognised by Who's Who Legal and Global Arbitration Review as a "Future Leader in International Arbitration".  Nathalie represents clients before key arbitral institutions including ICC, LCIA, SCC, ICSID and AAA, and in arbitrations conducted under the UNCITRAL Rules, ICSID and under foreign investment laws.   Nathalie has also acted in many arbitrations governed by a variety of different jurisdictions.  

Nathalie frequently appears before international tribunals in hearings on diverse procedural issues, interim measures, jurisdiction, and merits, and enforcement, set aside, and annulment proceedings.  She also advises clients on strategies, options, and tactics in anticipation of potential disputes.  Nathalie has particular experience in finance, telecommunications, manufacturing, gambling, insurance, construction and energy.  

Nathalie has spoken and published extensively on topics relating to international arbitration, arbitrator challenges, treaty changes, confidentiality, enforcement and climate change.  

Nathalie is qualified and Wales, and is a native speaker in French and English, fluent in Spanish and speaks Italian to a high level.  Prior to joining Addleshaw Goddard in 2020, Nathalie worked in the London office of another leading international law firm. 

  • representing a German car manufacturing company in an English law ICC €3 billion arbitration arising over a failed joint venture agreement
  • representing a Canadian manufacturing company in an Italian law ICC €60 million arbitration arising over a breach of contract
  • representing a group of investment funds in a Spanish law ICC €200 million arbitration arising over a shareholders' agreement dispute
  • representing an Asian investment fund in treaty proceedings against a European state
  • representing an individual in €30 million anti-arbitration injunction in the English High Court and the Court of Appeal, as well as in the related arbitration proceedings


  • University of Oxford (2001) BA (Hons) Modern Languages
  • Nottingham Law School (2002) Postgraduate Diploma in Law
  • Nottingham Law School (2003) Legal Practice Course