After graduating from EDHEC Business School in 1997 with a Master's degree in Management and Finance, he began his career at Colas as assistant to the Chief Financial Officer in the United States. He then held several positions in various American subsidiaries, including that of Administrative and Financial Director of the subsidiary in Alaska, Colaska.
In 2004, he returned to France to become Project Manager at Aximum, before taking charge of the administrative integration of a group of newly-acquired subsidiaries.
Between 2007 and 2009, he joined the internal control department at Colas, where he set up the Group's internal control system. 
In 2010, he became Administrative Director for the Northern Europe zone.
In 2017, Grégory joined Colas Rail as Chief Financial Officer.