About Us
Based at the heart of a strategic crossroads in Southeast Asia, the firm operates in an environment where legal matters frequently extend beyond national borders. From its inception, Ad Litem has been structured to handle cases with a strong international dimension, involving coordination between Thai law, French law, and more broadly, foreign legal frameworks.
Its creation stems from a field observation: the shortage of firms capable of effectively combining local expertise with a global understanding of legal issues. Ad Litem addresses this need by developing an integrated approach, ensuring the complete management of cross-border cases, both in advisory and litigation.
Our Team
The experts by your side
Thatsanavanh Banchong (Kai)
Co-Founder & Legal Adviser
Co-founder of Ad Litem with over 20 years of professional experience in Thailand. Specialised in international and intercultural legal environments. Trilingual: French, Thai and English.
Christophe Larrouilh
Co-Founder — Of Counsel — Paris Correspondent
Paris Bar attorney specialising in international private law and corporate law. French correspondent of Ad Litem, representing clients before French courts nationwide.
Kongwud Worasart
Co-Founder — Thai Bar Attorney
Thai Bar attorney with over 20 years of experience. Practises mainly in labour law, real estate litigation, corporate law and succession matters. Bilingual: Thai and English.
Pongsit Thepkraiwan
Partner — Thai Bar Attorney
Thai Bar attorney with over 20 years of experience. Practises in family law, medical law, labour law, immigration and succession matters. Recognised expertise in litigation.
Pimonporn Suriya
Partner — Thai Bar Attorney
Thai Bar attorney specialising in corporate law, tax law and family law. Known for her commitment, rigour and precise case follow-up. Bilingual: Thai and English.
Phubate Phromchaisri
Partner
Thai Bar attorney specialising in criminal law with significant litigation experience. Also practises civil law, including real estate disputes and family law. Point of contact in southern Thailand.
Key Figures
Since its founding in 2025:
200+
Cases handled
3
Languages spoken
6
Lawyers & advisers
2025
Year founded
Over 200 cases handled, both in advisory and litigation, across diverse areas including immigration law, family law, criminal law, real estate law, and international business.
A practice marked by a high proportion of contentious cases, particularly in criminal, family, and commercial matters, involving effective representation before Thai courts.
A client base primarily composed of French-speaking and international expatriates facing complex legal issues in a foreign context.
Regular involvement in cross-border situations requiring coordination of multiple legal systems and jurisdictions, particularly between Thailand, France, and other countries.
Our Background
Ad Litem draws on a team with complementary backgrounds, combining:
Expertise in international cooperation and intercultural legal strategy, developed through numerous transnational projects in Asia and Europe.
Hands-on legal practice for expatriates, covering areas such as family law, real estate disputes, commercial litigation, and criminal proceedings.
Close collaboration with experienced Thai lawyers registered with the local bar, ensuring thorough command of national procedures.
A partnership with Maître Christophe Larrouilh, Paris Bar attorney, enabling full management of cases under French law or with a Franco-international dimension.
This organisation enables effective intervention on complex cases requiring coordination between multiple legal systems.
