Cultural mediation is imperative in industrialized societies by moving closer art and the culture to the citizens. The museum does not escape this movement of cultural democratization and democracy which blows on the cultural institutions, both in Quebec and elsewhere in the world. As such, the educational departments of Quebec’s museums integrate more and more cultural mediation into their practices and Quebec’s universities offer from now programs going hand in hand with the requirements of professionalization of the domain. But what is museum mediation ? In what does it distinguish itself from cultural mediation ? What are their theoretical and conceptual foundations ? To answer these questions is crucial because the fact of knowing better and of understanding the foundations of the domain establishes the first stage towards the professionalization of museum mediator as a job, an emerging profession.