JEAN LUCIANI The object of this article is to show how historically, the organisation of the placement of workers in France has taken place under the influence of two contradictory logics : a local logic resting initially upon the principle of a zone of legal competence relating to economic activity and a professional logic linked to the instauration of the principle of freedom of work resting upon the principle of economic competence. The later logic is progressively translated from a defence of the trade ("metier") into the attempt, by the union movement, to take it over. The instauration of free and obligatory placement in the larger towns (law of 1904) brings to a close the domination of this logic. We advance the hypothesis that the construction of a labour market - the translation of the pre-eminence of place over trade - thereby becomes realisable.