Article Five of the United States Constitution describes the process whereby the Constitution, the nation's frame of government, may be altered. Altering the Constitution consists of proposing an amendment or amendments and subsequent ratification. Amendments may be proposed either by the Congress with a two-thirds vote in both the House of Representatives and the Senate or by a constitutional convention called for by two-thirds of the state legislatures. To become part of the Constitution, an amendment must be ratified by either—as determined by Congress—the legislatures of three-fourths of the states or State ratifying conventions in three-fourths of the states.