William is a dual French and English national, bilingual, and one of the most experienced international family lawyers practising in London today. With over two decades in family law, his practice sits at the intersection of English and European legal systems, and he knows both from the inside.
He is a widely acknowledged expert on European family law, and a significant part of his practice has a Francophone dimension: acting for French-speaking clients, advising on cross-border disputes between England and France, and navigating the jurisdictional questions that arise when the two legal systems. Most of his cases involve high-net-worth assets.
William is Vice-President of the International Academy of Family Lawyers (European Chapter), a trained mediator, and a regular voice in the press, quoted across the broadsheets in both England and France, and a contributor to national radio and television in both countries. He writes frequently on international family law for a wide range of publications and speaks at international conferences.
William has handled some of the most technically demanding international family law cases before the English courts, including matters that have established or predicted significant points of law.
He has acted in divorces involving complex asset structures spanning multiple jurisdictions. He has negotiated capitalised maintenance payments against senior figures in global investment banking, advised on prenuptial agreements where parties come from very different financial worlds, and secured a successful arbitration outcome in a children relocation case to Europe.
William has been recognised in the leading legal directories for many years as a specialist in international family law, European jurisdiction, and high-net-worth matters.
"Thinks deeply and critically about cases like nobody else. Completely on top of what his clients want and what they need, and creative and tactical in how to achieve that."
Legal 500, 2023
"Offers clear and robust advice to clients, and is always thinking about tactical approaches."
Legal 500, 2025
"Of all the solicitors in London, he has the best knowledge of European and cross-border issues."
chambers uk, 2017
"Reassuring — but also quite business-like. A fighter when he thinks it's the right thing to do."
Chambers Global HNW, 2017
"Stunning in his commitment."
Legal 500, 2015
R v R [2025] EWHC 3180 (Fam)
Khreino [2000] — successful wife; English court's powers to freeze family assets
M v V [2010] — successful husband; validity of French jurisdiction agreement on maintenance
EDG v RR [2014] — successful mother; cross-border enforcement of maintenance, which correctly predicted a later European Court of Justice ruling
"Deals with proceedings sensitively but with appropriate firmness. Excellent knowledge of the international issues involved, sensitivity and strength in negotiations."
Legal 500, 2025
"Very approachable and first class, with a substantial French practice."
Legal 500, 2024
"Quick to suggest practical solutions, rather than letting the parties dwell on who might be right or wrong."
Legal 500, 2017