This exceptional volume brings together the most influential work on contractarian moral theory for the first time. Due to developments in formal decision and game theory and an increasing dissatisfaction with traditional arguments for utilitarian and deontological moral theory, contractarianism is enjoying a dramatic resurgence in popularity. This collection is ideal for those who need to get to grips with contractarianism in its contemporary and sophisticated guise and includes the work of key thinkers such as Rawls and Gauthier.