For several centuries the game has been played according to the rules of the state system, juridical rules about the equality of states and geopolitical practices that focus on the inequalities of states. The framework and deeper implications of this type of world order have been best articulated by political philosophers, perhaps most persuasively by Machiavelli and Hobbes, but there are many versions of these “realist” themes, including in the thought of non-Western traditions. The state with its ability to mobilize resources, impose order within its borders, and most of all, by its capacity to wage war, sustain diplomacy, and establish temporary conditions of stability, has remained central to these analyses. Although many have grappled with the question of what privileges and immunities international officials should enjoy, no satisfactory theoretical framework has evolved. How has the issue evolved over time? How extensive is the problem? Why has the response been so ineffectual and the resolution been so intractable? Historians by disposition tend to look forward by going backward. Historically, international privileges and immunities, namely those bestowed on international functionaries, have influenced and become entwined with their diplomatic counterparts. Developments in diplomatic privileges and immunities have affected the immunities accorded international persons because diplomatic immunity developed as the standard and because “diplomatic” privilege is still used to define the privileges granted to some international officials. Hence the book would be of great help to those who are already concentrating on this subject and students of universities. This book has been designed so as to make the students, scholars and teachers informed of the principles of this subject.