In this dissertation, I propose a reconsideration within contemporary constitutional theory of the original functional character of the United States Constitution. The Founders designed the Constitution as a functional instrument of complex democratic procedures oriented toward substantive constitutional norms. It established procedural means that would function to achieve moral ends. Constitutional theorists too often analyze only one half of this functional equation. Moral constitutionalists understand the Constitution in light of its substantive ends, diminishing the importance of constitutional procedures. And contemporary originalists too often elevate constitutional procedures at the expense of the Constitution's moral principles. Yet, the Founders believed that the Constitution's carefully calibrated procedures would in fact operate to secure substantive constitutional ends. An evaluation of the Constitution's full functional character will improve our understanding of American political thought, our political and constitutional development, and the requirements of contemporary constitutional design. The current failure to capture the Constitution's functional operation is not unique to our own age. I begin in the first chapter by considering the pre-Civil War debates over the nature of the Constitution. I argue that those debates reflect an effort by Abraham Lincoln to salvage the original functional Constitution from those who prioritized either constitutional substance or constitutional process at the expense of the other. In defending the Union, Lincoln understood that maintenance of the original Constitution was a prerequisite for guaranteeing and extending individual rights. I follow with two chapters that critique contemporary originalism, specifically its elaboration of the "Madisonian System" and its normative defense of democratic procedures. My own approach is an effort to recover the original Constitution, but contemporary originalist accounts are often an obstacle to this recovery. I conclude by putting the original functional Constitution back together again. Drawing from sources rejected by both originalists and their criticsÌ¢ âÂ" specifically James Madison's analysis of the deficiencies of the Articles of Confederation and his recommendations for constitutional reformÌ¢ âÂ" I demonstrate that the original Constitution, is a functional document designed to achieve substantive results through democratic procedures, including democratic procedures in the states.