There are a number of different ways in which one can approach the phenomenon of international organization within the world order. The rationalist approach emphasizes the notion of a world order of states that is moving towards the more sophisticated types of order found within states. It is progressive in that it believes in the transformation of a society of states into a true world community based upon the application of universally valid moral and legal principles. In other words, the development of the United Nations into a real world authority is seen not only as beneficial but also as, in the long run, inevitable. This is to be accomplished by the gradual increase in the influence and responsibility of the organization in all fields of international peace and security. Thus international organizations have a profound substantive as well as procedural purpose, and are intended to function above and beyond mere administrative convenience. To put it another way, the rationalists emphasis the role of such institutions as active performers upon the world stage rather than as mechanisms to greater efficiency.

Another general line of approach is the revolutionary one, which regards international institutions in terms of specific policy aims. Here, the primary aim is not the evolution of a world community of states based upon global associations as perceived by the rationalists, but rather the utilization of such institutions as a means of attaining the final objective, whether it be the victory of the proletariat or the rearrangement of existing states into, for example, continental units.

The third approach which may be noted is exemplified by the doctrine of realism. This centers its attention on the struggle for power and supremacy and eschews any concern for idealistic views. The world stage is seen as a constant and almost chaotic interweaving of contentious state powers, and international institutions are examined within the context of the search for dominance. Both the league and the UN were created to reinforce the status quo established after the world wars, it is stressed, although the latter institution is now seen as reflecting the new balance of power achieved with the growth of influence of the states of the third world. Since what can be described as a world order is merely a reflection of the operation of the principle of the balance of power, realists see the role of world organizations as reinforcing that balance and enabling it to be safely and gradually altered in the light of changing patterns of power; although, to be accurate, their overall attitude to such organizations is usually characterized by cynicism, as the inherent weaknesses in these organization have become apparent.

A more hopeful way of looking at the international institutions is to concentrate upon those areas where the interdependence of states has impelled them to create viable organs for co-operation. By this means, by identifying such subjects for international agreement, it is hoped to be able to encourage growing circles of cooperation which may eventually impinge upon the basic political areas of world peace. This functional approach appears as a cross between the nationalist and realist trends and is one much examined in recent years.  This approach also emphasizes the pattern of institutional behavior and the operations of the relevant bureaucracies, including the way in which the tasks set for the organization are identified and completed. Decision-making analysis is another useful tool in this area

It is also possible to examine international organization in a variety of other ways, ranging form historical and comparative exposition to analysis of the legal rules underlying the establishment and operations of the particular institution.

Because of the great diversity of international and regional intergovernmental organizations, ranging from the United Nations to the North Atlantic Treaty Organization and the International Labour Organization, great difficulty has been experienced in classifying the relevant material. In this chapter, the simplest method of division into institutions of a universal character, regional institutions and the legal aspects of international institutions will be adopted. Within the relevant categories, the particular functions of different organizations, as well as their varying constitutional framework, will be briefly noted

The Chief functions of international organizations:

At present international organizations perform many functions and their functions are constantly increasing. Due to paucity of space it is not possible to mention here all the functions performed by international organizations. It will suffice to note here only those functions which are main in principle and which include other functions. Such functions are the following:-

I.One of the main functions of international organizations is keeping intact the sovereignty of states and despite their different social systems, they establish and expand peaceful cooperation among them.

II.The second main function is to ensure that the competition going on among the individual states remains peaceful.