This article presents and critically analyzes the liberal conception, the democratic conception and the critical conception of media pluralism. Each of them attributes to this concept a particular function and proposes a model of organization and functioning of the media that allows the realization of such function. In the context of a system subject to accelerated dynamics of technical and economic transformation, it is a model of institutional pluralism that recognizes the functional diversity of communication platforms (television, radio, press, Internet) and allows for differentiated regulation of them that is best able to adequately distribute communicational power in a democratic society.