Mathieu is currently serving as Deputy Vice-Director - Technical Division of the Service de Soutien de la Flotte (SSF). Previously he has served as the Internal Quality and General Management Officer in the Logistic Support Ship Programme Division at the Organisation for Joint Armament Co-operation (OCCAR) and the French Naval HQ in the Armament Programme Division with responsibility for the Logistics Support Ship Programme. His operational experience includes as Engineer Officer on the Flagship Tanker "Somme" and at NATO's Joint Forces Command Naples as DCOS Resources.