Over the course of the past two centuries, more than 10,000 amendments have been proposed by the method stipulated in Article V of the Constitution. Amazingly, only 33 have garnered the required two-thirds approval from houses of Congress, and only 27 were ultimately ratified into law by the states. Despite their small number, those amendments have revolutionized American government while simultaneously legitimizing and preserving its continued existence. Indeed, they have dramatically altered the relationship between state and federal authority, as well as between government and private citizens. Kyvig reexamines the creation and operation of Article V, illuminating the process and substance of each major successful and failed effort to change the formal structure, duties, and limits of the federal government. He analyzes in detail the Founders' intentions; the periods of amendment activity during the 1790s, 1860s, 1910s, and 1960s; and the considerable consequences of amendment failure involving slavery, alcohol prohibition, child labor, New Deal programs, school prayer, equal rights for women, abortion, balanced budgets, term limits, and flag desecration. Ultimately, Kyvig demonstrates that so-called "constitutional revolutions" can only endure through formal amendment; without it such sea changes as the New Deal are likely to be temporary amidst the shifting winds of political fortune. That truth underscores the centrality of the amendment process to American constitutionalism, sheds light on the "amendment fever" that swept through the 104th Congress, and better prepares us to deal with such initiatives in the future.