Construcciones y Auxiliar de Ferrocarriles is a Spanish publicly listed company which manufactures railway vehicles and equipment and buses through its Solaris Bus & Coach subsidiary. It is based in Beasain, Basque Autonomous Community, Spain. Equipment manufactured by Grupo CAF includes light rail vehicles, rapid transit trains, railroad cars and locomotives, as well as variable gauge axles that can be fitted on any existing truck or bogie.

Solaris Bus & Coach sp z o.o. is a Polish manufacturer of public transport vehicles, with its headquarters in Bolechowo-Osiedle near Poznań. It is a subsidiary of Spanish rolling stock manufacturer CAF with a market share for electric buses in Europe of about 18%.