The President of the United States frequently signs international agreements but postpones ratification pending Senate consent. Under international law, a state that signs a treaty subject to later ratification must avoid acts that would defeat the treaty’s object and purpose until the nation clearly communicates its intent not to join. As a result, the President in signing assumes interim treaty obligations before the treatymaking process is complete. Despite the pervasiveness of this practice, scholars have neglected the question of its constitutionality. As this Article demonstrates, the practice is unconstitutional. Neither the text, structure, nor history of the Constitution supports the practice. Nor can the practice be justified under the President’s authority to enter sole executive agreements or as a longstanding practice in which Congress has acquiesced. The result, ironically, is that the President often acts unconstitutionally when employing the treatymaking process outlined in Article II of the Constitution. Yet the President need not avoid the Article II process to cure this constitutional defect. The President avoids constitutional violation by consenting to international agreements through means other than signature subject to ratification.