The new charter of government agreed upon in Philadelphia in 1787 faced the daunting challenge of approval by conventions in each of the states. Immediately there arose one of the most bitter controversies in American history, much of it fought in pamphlets and the press. In this verbal barrage, the papers published by “Publius” in New York stood out with special brilliance. Between October 1787 and May 1788, eighty-five articles in defense of the new Constitution soon attracted attention far beyond New York’s borders, for they were clearly the work of a masterful politician. When published later in book form as The Federalist, they were found to be the joint effort of Hamilton, Madison, and Jay. While the papers are frankly campaign documents, and had a questionable impact on the ratification of the Constitution, they were the first and still the most important discussion of the fundamental principles of the federal government of the United States. Their brilliant analysis makes The Federalist a work of major importance in the history of political philosophy and the theory of representative government. The selections here consider major points of contention in the new Constitution.