Mr Stephen Fietta KC > Fietta LLP > London, England > Lawyer Profile

Fietta LLP


Stephen Fietta KC is the firm’s founder and principal. He is ranked by Chambers Global Directory as one of the world’s top public international law practitioners. He is included in The Legal 500 Hall of Fame as an individual who is “at the pinnacle of the profession” in Public International Law.

He has practised at the forefront of public international law, whether within government or private practice, for more than 20 years. He has advised on cases before the International Court of Justice (ICJ), International Tribunal for the Law of the Sea (ITLOS), European Court of Justice, European Court of Human Rights and multiple domestic courts. He has one of the world’s most prolific and longstanding practices in investment arbitration, having appeared in more than 30 pending and decided cases under the World Bank (ICSID), UNCITRAL and other rules.  He has won some of the largest or most notable investment arbitration awards over recent years.

Before establishing Fietta in 2015, Stephen co-founded the world’s first specialist public international law firm (Volterra Fietta) in 2011. Prior to that, he was a partner specialising in public international law at a leading US and global law firm. Both of those practices were top-ranked at the time. Stephen regularly manages large teams of lawyers (including co-counsel), experts and witnesses in multiple jurisdictions.

Stephen is a Visiting Senior Lecturer at King’s College, London. In January 2015, Stephen was awarded the Smit-Lowenfeld Prize by the International Arbitration Club of New York for the best article published globally in the field of international arbitration, entitled Public International Law, Investment Treaties and Commercial Arbitration: an emerging system of complementarity? Stephen has co-authored (with Dr Robin Cleverly) A Practitioners Guide to Maritime Delimitation, published in March 2016, which has subsequently been cited before both the ICJ and ITLOS.


Fietta LLP, principal (2015 onward); Volterra Fietta, co-founder and principal (2011 to 2015); Latham & Watkins, partner (2009 to 2011), senior associate (2005 to 2008); Herbert Smith, associate (2002 to 2005); United Kingdom Government, lawyer (1997 to 2002), (with 18-month secondment as UK National Expert to the European Court of Human Rights in Strasbourg, France (2001 to 2002)), Herbert Smith, associate (1997), trainee solicitor (1995 to 1997)


English (native), French and Italian (reading and conversational)


Queen’s Counsel (appointed January 2019)

Solicitor-Advocate (Higher Courts Civil Proceedings) (2016)

Admitted to practise in England & Wales (1997)

B.A. (1993) and M.A. (1994) in Law, University of Cambridge, Winner, Cambridge University Prize for Commercial Law

Legal Practice Course (Distinction), University of Law, Guildford

Stephen is a Visiting Senior Lecturer at Kings College London, where he teaches the MA course “Geopolitics, Territory and Security”

Stephen has also lectured on various public international law topics on LLM and MSc courses at University College London (UCL), the London School of Economics (LSE) and University of Southampton


Cycling, tennis, skiing, history, philosophy and writing 

Lawyer Rankings

London > Dispute resolution > International arbitration

(Leading individuals)

Stephen Fietta KCFietta LLP

Boutique law firm Fietta LLP houses a dedicated international arbitration and public international law (PIL) practice that is widely respected for its investment disputes credentials. The ‘strategicStephen Fietta KC is regularly instructed by sovereign states to act in highly sensitive PIL matters, including some of the world’s highest profile territorial claims; and Jiries Saadehhas vast experience in investment disputes‘. Ashique Rahman is a partner as of July 2022, while Laura Rees-Evans and Oonagh Sands are the counsels to note.

London > Dispute resolution > Public international law

(Hall of Fame)

Stephen Fietta KCFietta LLP

The strongest PIL boutique in London‘, Fietta LLP has ‘vast experience in PIL matters‘. Dedicated to PIL and international arbitration work, the practice is routinely instructed by sovereign clients in their most sensitive PIL matters globally; and in contentious work, the team represents both investors and respondent states in investment arbitration. With ‘remarkable knowledge of PIL‘, founding partner Stephen Fietta KC regularly acts for sovereign states in high-profile territorial disputes; and Jiries Saadeh, ‘an absolute star of his generation‘, represents state and investor clients in international investment treaty cases. At counsel level, Australian lawyer Ashique Rahman is a founding board member of the Young Public International Law Group, a network of PIL practitioners; and Laura Rees-Evans and Oonagh Sands also both assist with complex PIL issues.