Construcciones y Auxiliar de Ferrocarriles, S.A. designs, manufactures, and sells rolling stock and rail components worldwide. The company operates through Railway and Bus segments. It offers high speed trains, regional trains, commuter trains, metros, LRV's and tram-trains, trams and light metros, and locomotives, as well as electric, trolley, hydrogen, and hybrid buses. The company also provides equipment and components, such as wheel sets, wheels, axles, and gear units, as well as after-sales services, including technological advice and inspection guidelines; and traction systems and converters, energy storage systems, and control and communication systems, as well as financing solutions. In addition, it designs, manufactures, supplies, and maintains railway signaling systems. Further, the company is involved in the provision of maintenance, and refurbishment and upgrading services; data collection, storage, and processing and analysis services; management of spare parts and workshop equipment; and technical support and consultancy. Additionally, it develops turnkey solutions that cover a range of activities, such as viability studies, civil works, electrification and signaling, maintenance, and the operation of the system. The company was formerly known as Compañía Auxiliar de Ferrocarriles S.A. and changed its name to Construcciones y Auxiliar de Ferrocarriles, S.A. in 1971. Construcciones y Auxiliar de Ferrocarriles, S.A. was founded in 1892 and is headquartered in Beasain, Spain.