Keolis is a private operator of public transport in the passenger transport sector. The company operates in the field of passenger transport by metro, tramway, bus and coach, bicycle, transport for people with reduced mobility, car-sharing and car-pooling, river and maritime shuttles, autonomous shuttles, cable cars, funiculars, trolley buses and airport services. 

Keolis, through its subsidiary EFFIA, is also number 2 in the parking market in France. Owned 30% by the Caisse de dépôt et placement du Québec and 70% by the Société Nationale des Chemins de Fer Français (SNCF), the Paris-based company has recently become part of SNCF Mobilités.

The group defines itself as a multi-modal player: 

In France, Keolis operates the network mainly Transport Bordeaux Métropole, (TBM), the network of the TCL (Lyon Public Transport), but also the STAR (Public Transport Service of the Rennes agglomeration). 

Internationally (which represents 45% of its turnover), it is the operator of the Stockholm city buses, the Boston commuter trains, the Las Vegas bus network, the Melbourne and Manchester tramways and many others.