From within a “systemic approach” to deliberative democracy, political parties can be seen as crucial actors in facilitating deliberation, by playing epistemic, motivational, and justificatory functions that are central to the deliberative ideal. However, we point out that if we assume a purely outcome-oriented conception of the role of parties within a deliberative system, we risk losing sight of a central tenet of deliberative democracy and of its distinctive principle of legitimacy, namely, that citizens must be able to exercise critical (...) reflection on the grounds of democratic decisions. We argue that parties have a special responsibility in making a deliberative system meet this requirement, and that such special role can be fulfilled only if parties’ programs, values, and strategies are shaped through intra-party deliberation. On the grounds of this discussion, we define a model of intra-party deliberation that is based on the principles of mutual acceptability, pluralism, and publicity. (shrink)