Graduated as lawyer, Gilles Mugnier has held legal management positions in the energy and rail transport sector. After his studies in France and Switzerland, he first worked as a lawyer for Gaz de France and then for EDF, mainly in charge of international files.
In 1999, he joined the company Rexel (PPR group) to take charge of international cases and financial law in the legal department.
In 2004, he moved to the transport sector by joined the Keolis Group as Legal Director in charge of international and rail activities. He created the international legal department and supervised cases covering 11 countries. He was also Managing Director of Keolis Nederland from 2010 to 2011.
In 2011, he moved to SNCF as Deputy Consul General. In this context, he played a significant role in the legal supervision of the 2015 and 2020 French rail reforms. In 2020, he joined the SNCF group's international department as Director of International Affairs, in charge of major projects and contracts.