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Oonagh Sands

Fietta LLP


Oonagh Sands is a dually-qualified English and US-lawyer and Senior Associate


Oonagh has significant experience representing sovereign States and their State-owned entities, as well as private individuals and entities, before leading world dispute resolution fora. She has represented clients before the International Court of Justice, the Permanent Court of Arbitration, as well as investor-State arbitral tribunals constituted under ICSID, ICSID Additional Facility, UNCITRAL, and ICC rules. In addition, Oonagh has counselled States on territorial and maritime boundary disputes, as well as issues arising under the law of the sea.

Prior to joining Fietta, Oonagh worked at major law firms in Washington DC and London. Oonagh has also worked for the United Nations Office of Legal Affairs in New York, the European Commission in Brussels, and the Institute of International Economic Law at Georgetown University Law Center in Washington DC.


French and Spanish


LLM Public International Law (Pass with High Merit) (2009-2010), University College London
LLM General Legal Studies (2002-2003), Georgetown University Law Center
Postgraduate Diploma EC Competition Law, (2001-2002), King's College London
French Civil Law (Distinction), (1999-2000), Université de Bourgogne
LLB (Jt. Hons) Common and Civil Law with French, (1997-2001), Queen's University Belfast

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