Xavier Nyssen


Xavier Nyssen is the immediate past Co-Chair of Dechert’s international dispute resolution practice. Since 1988, he has concentrated his practice in international arbitration and complex litigations, especially in the telecom, energy and pharmaceutical sectors.

He has acted as counsel in numerous arbitrations whether ad hoc or under the rules of the International Chamber of Commerce (ICC), the London Court for International Arbitration (LCIA) or the European Development Fund (FED). He is also well versed in proceedings for the enforcement and the annulment of arbitration awards and occasionally acts as arbitrator.

Mr. Nyssen also regularly advises foreign companies on procedures to collect evidence and to enforce foreign judgments and arbitration awards in France.

Before joining Dechert in 2005, he worked in New York and Brussels and was co-managing partner of the Paris office of an international law firm, where he was responsible for the Litigation department.

Mr. Nyssen has been consistently recognized by both Chambers Europe and Chambers Global for his "strong track record on arbitrations in the energy, pharmaceuticals and telecommunications sectors." He is listed in The Legal 500 France and Décideurs Stratégie Finance Droit. Sources described him as a client-oriented, technically gifted and creative practitioner who provides "very high-level advice on complex matters." In 2017, he was listed as a leading lawyer by The Who's Who Legal: France - Arbitration.

Contact details

+33 1 57 57 80 01

Areas of Practice


Year Qualified



Columbia Law School, LL.M.
University of Liège, M.A.


Advisory Board, Institute for Transnational Arbitration
Former Member of the Litigation Committee, International Bar Association
Belgian Center for Mediation and Arbitration (CEPANI)


Brussels, Paris and New York