Modern separation of powers doctrine reflects a theoretical stalemate. For the last generation, many courts and commentators have argued that the legislative, executive, and judicial powers should be exercised by three formally distinct branches, while others have contended that the doctrine permits mixing these powers so long as the underlying functions or purposes of separation of powers are realized Recent appeals to the Constitution's origins have only deepened, not resolved, the stalemate. The past can provide guidance in addressing this problem, Professor Flaherty suggests, but only if more rigorous methods of historical scholarship are employed Once that is done, a clearer, but more complex, picture of the original understanding of separation of powers emerges. That picture bears little resemblance to accounts which posit that the Framers reached a consensus on a formalist approach to separation of powers. Instead, American constitutionalists during the last three decades of the eighteenth century experimented with Whig ideas of mixed government, a republican commitment to legislative supremacy, and only late in the day embraced what we think of as separation of powers. Even then, the proceedings of the Constitutional Convention, the text of the Constitution, and the ratification debates indicate that the Founders generally agreed only that separation of powers should serve such broader functions as balance, joint accountability, and adequate governmental energy. Otherwise the doctrine remained underdeveloped, and many early applications of it violated formalist precepts. Americans seeking to remain faithful to the Founding, according to Professor Flaherty, should therefore abandon the formalist approach and instead apply the original separation of powers values to the different governmental circumstances we confront today. The President long ago replaced Congress as the branch that most threatens constitutional balance. The President's claim to electoral mandates resembles the type of simple accountability that the Founders came to suspect rather than celebrate, and the growth in federal and executive power make eighteenth-century concerns about governmental energy antiquated Translating Founding values into this modem setting requires a two-fold approach to separation of powers. First, the Supreme Court should require a high threshold before intruding into institutional arrangements established by the political branches. Second, the Court should only intervene to further the general goals originally attributed to separation of powers.