This volume makes available in an English translation the most significant part of Montesquieu's political, social and legal theory. About two-thirds of the volume has been translated from the Spirit of the Laws, not redone in English since the eighteenth century. That version was notoriously inadequate: Montesquieu's key terms were not rendered consistently; often his meaning was distorted by giving the nearest English eighteenth-century legal or institutional equivalent. Finally, English usage has changed so much that the eighteenth-century translation makes Montesquieu seem both quaint and obscure. This volume also includes substantial selections from the Persian Letters and the Considerations on the Causes of the Romans; Greatness and Decline. Although adequate translations of these works exist, it seemed advisable to maintain intellectual and stylistic consistency by providing English versions on the same principles as the Spirit of the Laws.