美国宪法(Constitution of the United States)
美国联邦政府体制的根本法，也是西方世界一个划时代的文件。它是正在实施中的最早的成文国家宪法，1787年由五十五位代表聚集於费城举行的一个会议中写成的，会议的名义是对美国第一部成文宪法「邦联条例」进行修改。由於许多州的批准是以许诺补充「人权法案」为条件的，使得该宪法的正式通过直到1791年才得到完全确认。这部宪法的设计者们特别关注於限制政府的权力和保障公民的自由。立法、行政和司法部门的分离，它们彼此之间的制约和平衡，以及对个人自由的明确保证，都是旨在达到权威和自由之间的平衡。第一条将全部立法权力授予国会－－众议院和参议院。第二条将行政权授予总统。第三条将司法权授予法院。第四条部分地谈到州际关系和各州公民的特权。第五条谈到修改程序。第六条谈到国债和宪法的至高无上的效力。第七条说明批准的条件。第十条修正案规定联邦政府仅有宪法授予它的权力；各州则除另有限制者外，拥有所有其他的权力。因此，联邦的权力是列举的，州的权力是概括的。州的权力常常被称为剩余权力。宪法修正案可由国会两院2/3的议员提出，或由国会根据2/3州议会的请求召开的一次会议提出。所有後来的修正案都是由国会提出的。国会提出的修正案必须经3/4的州议会批准，或由同样多的州的会议批准。从1789年以来已经有二十七项修正案被补充入宪法中。除最初的十项－－1791年的「人权法案」被采纳为一个独立的单位－－以外，其他影响深远的修正案包括︰第十三条修正案（1865），废除奴隶制；第十四条修正案（1868），法律提供公平审判和平等保护的原则；第十五条修正案（1870），保证不受种族影响的投票权；第十七条修正案（1913），规定直接选举美国参议员；第十九条修正案（1920），规定妇女选举权；第二十二条修正案（1951），限制总统的任期不得超过两届等。参阅civil liberty、commerce clause、Equal Rights Amendment、freedom of speech、judiciary和states' rights。
English version：
Constitution of the United States
Fundamental law of the U.S. federal system of government and a landmark document of the Western world. It is the oldest written national constitution in operation, completed in 1787 at a convention of 55 delegates who met in Philadelphia, ostensibly to amend the Articles of Confederation. Because ratification in many states hinged on the promised addition of a Bill of Rights, the Constitution was not fully certified until 1791. The framers were especially concerned with limiting the power of the government and securing the liberty of citizens. The Constitution's separation of the legislative, executive, and judicial branches of government, the checks and balances of each branch against the other, and the explicit guarantees of individual liberty were all designed to strike a balance between authority and liberty. Article I vests all legislative powers in the Congress—the House of Representatives and the Senate. Article II vests executive power in the president. Article III places judicial power in the hands of the courts. Article IV deals, in part, with relations among the states and with the privileges of the citizens, Article V with amendment procedure, and Article VI with public debts and the supremacy of the Constitution. Article VII gives ratification terms. The 10th Amendment restricted the national government's powers to those expressly listed in the Constitution; the states, unless otherwise restricted, possess all the remaining (or “residual”) powers of government. Amendments to the Constitution may be proposed by a two-thirds vote of both houses of Congress or by a convention called by Congress on the application of the legislatures of two-thirds of the states. (All subsequent amendments have been initiated by Congress.) Amendments proposed by Congress must be ratified by three-fourths of the state legislatures or by conventions in as many states. Twenty-seven amendments have been added to the Constitution since 1789. In addition to the Bill of Rights, these include the 13th (1865), abolishing slavery; the 14th (1868), requiring due process and equal protection under the law; the 15th (1870), guaranteeing the right to vote regardless of race; the 17th (1913), providing for the direct election of U.S. senators; the 19th (1920), instituting women's suffrage, and the 22nd (1951), limiting the presidency to two terms. See also civil liberty, commerce clause, Equal Rights Amendment, establishment clause, freedom of speech, judiciary, states' rights.