Formed in 1992 through the strategic merger of two historic French engineering consultancies—Inter G (established in 1946) and Christiani & Nielsen France—Groupe Ingérop has grown into one of Europe’s leading independent multidisciplinary engineering and consulting firms. Headquartered in Rueil-Malmaison (Greater Paris), the group is 100% owned by its management and employees, a governance structure that guarantees technical neutrality, agility, and long-term commitment. Ingérop employs more than 3,200 engineers, architects, and technical specialists across Europe, Africa, Latin America, and North America.

In the railway and mass transit sector, Ingérop acts as a tier-one lead designer (Maître d’Œuvre) and project management consultant (AMO – Assistance à Maîtrise d’Ouvrage). The firm has been at the center of France’s high-speed rail (LGV) expansion, including the LGV Rhin-Rhône, LGV Sud Europe Atlantique (Tours–Bordeaux), and the high-speed Rail Baltica project connecting Estonia, Latvia, and Lithuania to the European standard-gauge network, where Ingérop leads engineering design across key corridor packages.

In urban rapid transit, Ingérop is a primary engineering partner on the Grand Paris Express—the largest transport infrastructure program in Europe. The company is the lead engineering design manager for the 34-kilometer automated Metro Line 18 (connecting Orly Airport to Versailles), as well as delivering extensive underground stations, deep tunnels, and systems on Lines 15 West and 15 South. Globally, Ingérop has delivered modern tramway networks (Paris T3, T9, Strasbourg, Bordeaux, Zaragoza), automated metros (Rennes Line B, Santiago Metro in Chile), and innovative aerial transit systems including the Medellín Metrocable in Colombia.