Patrick Charaudeau defines himself as a semiologist and a researcher in Discourse Analysis. It is as such that he intervenes here. As a matter of fact he defines, on a tone which is not polemical, what conditions are necessary for the interdisciplinarity to come true. Two linguists – Dominique Maingueneau and Roselyne Koren – and a researcher in sciences of information and communication – Sylvie Leleu-Merviel – answer him, each specifying what cover the interdisciplinary and disciplinary notions, the first two by abounding – with some nuances – in the direction of Patrick Charaudeau's propositions, the last one by putting them in to the test of the scientific construction.