This book studies a central but hitherto neglected aspect of Rousseau's political thought: the concept of social order and its implications for the ideal society which he envisages. The antithesis between order and disorder is a fundamental theme in Rousseau's work, and the author takes it as the basis for this study. In contrast with a widely held interpretation of Rousseau's philosophy, Professor Viroli argues that natural and political order are by no means the same for Rousseau. He explores the differences and interrelations between the different types of order which Rousseau describes, and shows how the philosopher constructed his final doctrine of the just society, which can be based only on every citizen's voluntary and knowing acceptance of the social contract and on the promotion of virtue above ambition. The author also shows the extent of Rousseau's debt to the republican tradition, and above all to Machiavelli, and revises the image of Rousseau as a disciple of the natural-law school.