The right to dissent includes both the right to speak of what is right and wrong and the moral obligation to give good reasons for a particular statement. In a modern democratic society the right to dissent is one of the most fundamental rights. Inherent in the right to dissent, we find the paradoxical morality of modern society, which consists of a critical assessment of what should be deemed right or wrong. The right to dissent has to be secured through the civil rights of participation in political deliberation and the cultivation of these legal rights in the public spheres of a deliberative democracy. The ethics of dissent is developed in this book through a new interpretation of the German philosopher Jürgen Haberman' communicative ethics and his political philosophy. Freedom, the right to dissent, and thoughtful critique is emphasised in the concept of negative discourse ethics. This critical perspective is integrated in a broader interpretation of Haberman' theory of communicative action and related to the classical traditions of political philosophy -- Plato, Aristotle, Kant, Hegel, Kierkegaard, and Rawls. Larsen further develops the philosophical perspective in a sociological discussion of civil society, public spheres, politics, law and a globalising society, considered in relation to the classical tradition of sociology -- Marx, Weber, Durkheim, Horkheimer, Adorno, Marcuse, Bauman, Foucault, and Bourdieu.