For reasons that political scientists do not fully understand, American political elites are now more ideologically polarized than they have been since the end of World War I. This polarization–in combination with the rise of divided party government–has sweeping implications for the presidency. No aspect of executive-legislative relations is untouched. But also deeply affected are relations with the media, with thejudiciary, with the bureaucracy, and even the organization of the president's own staff. Presidential scholars are just beginning to grasp these changes. We face an enormous challenge but also a remarkable opportunity. The polarized presidency makes us confront a broader range of the institution's possibilities–and those of American democracy.