8. Article 119 pursues a double aim.
9. First, in the light of the different stages of the development of social legislation in the various member states, the aim of article 119 is to avoid a situation in which undertakings established in states which have actually implemented the principle of equal pay suffer a competitive disadvantage in intra-community competition as compared with undertakings established in states which have not yet eliminated discrimination against women workers as regards pay.
10. Secondly, this provision forms part of the social objectives of the community, which is not merely an economic union, but is at the same time intended, by common action, to ensure social progress and seek the constant improvement of the living and working conditions of their people, as is emphasized by the Preamble to the Treaty.
11. This aim is accentuated by the insertion of article 119 into the body of a charter devoted to social policy whose preliminary provision, article 117, marks, 'the need to promote improved working conditions and an improved standard of living for workers, so as to make possible their harmonization while the improvement is being maintained'.
12. This double aim, which is at once economic and social, shows that the principle of equal pay forms part of the foundations of the Community.
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39. The prohibition on discrimination between men and women applies not only to the action of public authorities, but also extends to all agreements which are intended to regulate paid labour collectively, as well as to contracts between individuals.