A graduate of the École Supérieure des Mines de Paris, Estelle Masclet has developed her systems expertise at the heart of SNCF Réseau, working in a variety of roles in Network Maintenance and Railway Traffic Operations. She joined SNCF in 2002, holding successive management positions: head of Electrical Signalling Operations, then Track Operations, followed by head of a Regional Operations Centre, HR Manager, and Production Manager, before becoming Director of the Rhône-Alpes Infrastructure and Traffic Operations Unit in Lyon. 

In 2021, she was appointed Managing Director of System Operations, where she focused on boosting network performance and transforming railway operations with a systems-based approach. In 2025, she became Deputy Managing Director, Operations and Industrial Programmes, at SNCF Réseau.