The essay, in reviewing the discussion of trade union representation in the private employment, proposes a decomposition of analysis, in relation to necessity to lower the different models in the contexts where the trade union express the power to negotiate. In particular, in reference to collective national negotiation of category, he prefers the thesis that rebuilds the trade union representation as associative representation, while the trade union representation into the single firms as institutional representation (in particular he recognizes the discipline on unitary trade union representations that takes the power from electoral consultation of all the workers in firm). Then the analysis of trade union representation, in reference to the notion of trade union in comparison more representative concerns, on one land, art. 39 of the Constitution and, on the other land, the remark that the collective contracts with legal effects ask "the contractual union" of trade union. Last, he proposes a law meant to generalize the experience of company trade union representations and to place the recall to the greater comparative representation on a mechanism both associative and electoral, in reference to assignment of functions submit by law.
Keywords: Trade union representation; Associative representation; Institutional representation; Trade union in comparison more representative; Collective contracts with legal importance; "The contractual union" of trade unions.