Société de Transports de l'Agglomération Stéphanoise, or STAS operates a public transport network and infrastructure in and around Saint-Étienne.

Its responsibility is to provide tramway, trolleybus and bus service in the fifty-three communes of the Saint-Étienne agglomeration.

[1] The company's official name, although not used is the TPAS and is a Société Anonyme with a capital of 17 700 000 euros.

Its main shareholder, Transdev is the parent company.

STAS maintains its rolling stock from three sites: and is also responsible for sites throughout the Saint-Étienne: The STAS providing a diverse array of service possesses a diverse fleet, of which includes: