The justification of political power is a prerequisite for its legitimacy. The book systematizes the manifestations of this liberal intuition and, with reference to John Rawls, develops the idea of generating legitimacy through public justification. On the one hand, it defends political liberalism as a theory of legitimacy suitable for pluralistic societies that helps to realize the normative potentials inherent in democratic institutions. On the other hand, it explores its boundaries, arguing that public justification does not address all citizens equally: the defenders of liberal legitimacy must be aware of the limited scope of their justificatory resources.