Adéa Celle
International Legal Counsel
Investment Treaty & ISDS Specialist
I provide legal insight and strategic support to States, law firms and international investors across the globe. I founded Vestaria Consulting to deliver flexible, high-level legal and political services in all aspects of investment treaty law.
Advisor to States
Legal and strategic advice on investment treaty reform, negotiation, and dispute management
I help States define and negotiate their international investment agreements — including bilateral investment treaties in ways that protect their sovereign interests while ensuring legal certainty and maintaining the country’s attractiveness to foreign investors. I provide legal and strategic support throughout the treaty lifecycle: from the review and redesign of treaty models, to the negotiation of new or revised agreements, and to the management of disputes under existing frameworks. This includes treaty interpretation, risk assessments, and guidance on how to engage with investors constructively or defend the State’s position in arbitration.
Legal counsel for law firms
Expertise in investment treaty law and arbitration
I act as independent counsel for law firms seeking ad hoc or ongoing support in investment treaty cases or international arbitration. With extensive experience and a deep knowledge of international investment law, I contribute efficiently and discreetly to the legal and strategic challenges your team may be facing.
Advisor to International Investors
Legal and political advice on treaty protections and investor-States risks
I help international investors understand and secure their rights under international investment agreements. I provide legal advice and strategic insight before, during, and after disputes. This includes treaty interpretation, risk exposure assessments, and guidance on how to engage with host States.
About me
I am an international lawyer specialised in investment treaty negotiation and investor–State dispute settlement. I am based in Lyon, France — a strategic location between Paris and Geneva.
I have worked in both high profile public institutions and law firms, including as a treaty negotiator on behalf of the European Union. I now put my 15 years of experience and legal insight at the service of clients dealing with complex questions of investment treaty protection and investor–State arbitration.
My work combines legal precision, strategic thinking, and a deep understanding of the public and private dimensions of cross-border investment.
I am a graduate of King’s College London (LL.B. in Law), Sorbonne University – Paris I (Maîtrise in Private Law), the College of Europe in Bruges (Master’s in European Law), and emlyon business school (Executive Business Course).