Bruce Ackerman has described three occasions upon which the U.S. Constitution underwent a massive transformation, and one failed attempt to bring about such a transformation. Only one of the major transformations that actually took place took the form of amendments to the Constitution, and even these did not follow the procedures laid down in the Constitution. This has led Ackerman to propose alternative amendment procedures. In this article, I discuss the "ideal" procedures for amending a constitution, Ackerman's proposal, and my own preferred alternative. © 1999 Kluwer Academic Publishers, Boston.