Chapter 14 examines international legitimacy as a system of reference that influences how actors (primarily states and individuals) experience meaning in the international sphere and, to some degree, at the national level. As a way to unpack what to understand in how a sense of legitimacy can function as a reference and framework of meaning in an international system, this chapter focuses on three points: how the start of an international order can impact its legitimacy, which leads me to argue that it can happen in three ways: force, negotiation, and a combination of the two, each of these ways having an impact on how the sense of legitimacy of international order is perceived; how, once in place, the sense of legitimacy in an international system influences actors (their behavior, identity and values); and how the scope and depth of legitimacy internationally can vary with time and circumstances.