Sam is instructed by individuals, families, and trustees across the world to address issues arising from divorce, and to assist in the preparation of pre- and post-nuptial agreements. He also has extensive expertise in complex parental disputes, with a particular emphasis on international relocation.

His clients range from the sports and entertainment industries to the City and international community, with a particular emphasis on the US, South America, Russia and the Middle East.

Sam is known for his complete discretion, commercial advice and ability to achieve swift, best-outcome solutions for his clients. He also has extensive experience in ‘private court’ based arbitration for family disputes.


Sam is acknowledged as one of the leading lawyers of his generation, and featured in The Lawyer’s Hot 100 list 2018.”

Spear’s says of Sam: “One of the UK’s leading partners, Longworth is popular among clients, referrers and peers alike. He is ‘very highly regarded not only for his personal qualities but also his excellence as a lawyer,’ a contemporary says.” It continues: “Peers describe the astute litigator as tough, ‘charismatic and assertive’, with a ‘calming approach’ when needed. ‘[He’s] never one to shy away from a challenging client or opponent, or a complex case,’ echoed another.”

Chambers praises Sam as “a great tactician and a good fighting litigator. He’s very clear and forthright in his advice, and commands total respect from his clients.”

Chambers states: “He is a deep thinker tactically and a hard fighter. He is experienced advising on high-value matrimonial finance cases, Schedule 1 proceedings and nuptial agreements.”

The Legal 500 comments that Sam stays “very calm under pressure”, with prior editions recognising his “detailed knowledge of multi-jurisdictional divorces”.



Sam’s recent reported cases include:

  • Kelly v Pyres [2018] EWCA Civ 1368 (Court of Appeal decision on divorce jurisdiction and forum shopping)
  • In the matter of C (Children) [2018] UKSC 8 (Supreme Court decision regarding the international relocation of children following separation)
  • U v J (No.2)(Domicile) [2017] EWHC 449 (Fam) (multi-jurisdictional divorce forum dispute).
  • J v U [2016] EWHC 2481 (Fam) (children forum shopping)
  • AB v CD (No.2) [2016] EWHC 2482 (Fam) (defence of £800,000 costs claim)
  • BR v VT [2015] EWHC 2727 (Fam) (interim order for sale of family home)
  • S v G [2015] EWFC 4 (international relocation)


After training in London, Sam spent time at a leading regional practice before joining Stewarts in 2007, where he became partner in 2013.


Sam is a regular commentator on developments in family law, divorce planning, divorce arbitration and international relocation. He is a presenter for Lexis Nexis, and has spoken at various international conferences.

Accreditations and Memberships

Sam is a fellow of the International Academy of Family Lawyers and Vice Chair of The International Family Law Committee of The American Bar Association Section of International Law. He is an active member of the IBA and Resolution.