For most observers, Iraq's recent elections were an important first step on the road to democratic normalcy. However, three related outcomes—the political marginalization of Sunni Arabs, the electoral gains made by Shi'a religious parties, and the triumphant performance of the Kurds—render the task of crafting Iraq's permanent constitution significantly more problematic. In this paper, we examine the implications of these election results for the design of Iraq's federal system. Our focus is on the character of the subunits in any future system, specifically on whether Iraq should adopt a form of territorial federalism based on the country's existing eighteen provinces (as most scholars argue) or whether a form of ethnic, or "plurinational," federalism based on five regions would be better able to address the very significant problems created by the election results. After assessing the relative merits of the various proposals for a federal Iraq, we conclude that a system based on five broad regions, though not ideal, is the least bad of the options available.