Abstract: At least since the late eighteenth century, constitutions have been understood as emanations of the will of “the People,” as the ultimate expression of an inherent popular sovereignty. In the form of theories of constituent power, accounts of constitutional foundations blended notional or conceptual “descriptions” of the People, which anchored the political legitimacy of constitutional orders in the idea of hypothetical consent, with empirical claims that the nation’s actual people were represented in constitution-making processes through elected delegates and thereby were the authors of and gave consent to its fundamental law. As part of the third wave of democratization, there was an important shift in what popular participation consisted of—from indirect participation by elected representatives to direct, popular participation in the constitution-making process. As a matter of constitutional process, this led to the growing practice, and expectation, that major constitutional changes should be ratified through referenda.