The previous two chapters established that decision-making within the Convention involved a wide range of interests and views, which were led to engage with each other in a process of mutual accommodation that eventually issued in a remarkable consensus. Yet this analysis focused on the Convention’s internal dynamics, or in other words on the supranational level of the two levels that can be distinguished in the democratic constitutionalization in the European Union. Complementary to these findings, this chapter turns to the relations of the Convention with the domestic level. As is indicated in Chapter 2, a consensus at the supranational level does not suffice for democratic constitutionalization beyond the nation-state. It also requires this agreement to become the object of consent in the national constituencies. For this, the theory of two-level democratic constitutionalization requires the political will-formation by the citizens, which remains located in the domestic sphere, to be affected by the arguments that are transmitted through their representatives at the supranational level (cf. Savage and Weale 2009). Departing from an initial conception of the national stakes in the European negotiations, these representatives report back into the domestic debate about how this conception is received by other national constituencies and the alternative views that are put forward there. Thus, a dynamic is expected to unfold in which processes of domestic will-formation gradually accommodate to the negotiations at the supranational level, which they thereby provide with new, revised input that allows the terms of the negotiations to shift. In that light, any shifts in the positions of the supranational negotiators would seem likely to be backed up by a corresponding shift in the opinion of their constituencies, or at least by a conviction on the part of the representatives that their constituencies could be persuaded to change their opinion. Eventually, the negotiation result thus emerges as the expression of an overlapping consensus between the different domestic debates.