The components industry in Spain grew alongside the automotive industry, and from the beginning, it was developed by non-Spanish companies. Whilst Spain was a protected market, the established assembly operations - Renault, Peugeot, Citroën and Fiat - encouraged their own suppliers to set up plants there in order to supply locally made components. Since the freeing of the market, more manufacturers have come in and they too have encouraged their suppliers to invest heavily in the Spanish industry. Politically they wanted suppliers in Spain so that they could increase the local content proportion, but the economic advantages of close proximity and low labour costs were just as important. An established supplier producing components of a guaranteed quality could export these to other European plants operated by the assembler.