This section reviews the complete range of international organizations. The conventional categories used are first examined, then various ways of distinguishing between the many kinds of organization and degrees of "internationality" are considered. The problem of borderline cases is discussed, together with non-organizational substitutes for organizations and possible alternative forms of organization. Quantitative information on the growth of international institutions and indicative data on regional organizations are also presented.

A major difficulty in obtaining some understanding of international organizations is the variety of organizational forms which need to be considered. Abstract classification schemes, particularly when simplified for convenience, tend to conceal the existence of well-developed groups of organizations with distinct features. The approach employed here has been to use several different ways of breaking up the range of organizations and to cite several examples of organizations of any particular type.

The intent is not to put forward a new systematic classification of international organizations but rather to facilitate an appreciation of the variety of bodies which could be incorporated into any such scheme. A comment on the three conventional categories used (intergovernmental, international non-governmental non-profit, and multinational enterprises) is thus a valid point of departure. The second breakdown of international organizations is developed on the basis of the terminology used in the actual title of the body. The intent here is to show the limitations of this obvious, but somewhat superficial, approach, as well as its value in distinguishing between some kinds of organization. The scheme developed is based on the relationship between such bodies and the meetings by which they were created.

Another categorization used is based on the structural peculiarities of some kinds of organization. Bodies are distinguished in terms of their hybrid character, dependent character, semi-autonomous character, relationship to leadership, regional orientation, functional orientation, heterogeneity of membership, structural complexity, or minimal structure.

Some international organizations may also be usefully characterized by the special emphasis they give to a particular mode of action. Others may be distinguished by the specialized nature of their preoccupation (as contrasted with any more conventional classification by subject). A significant number of bodies called "international" can also be usefully distinguished in terms of peculiarities in their geographic orientation or distribution of membership.

In addition to the above rubrics, there are a number of groups of organizations with other special characteristics such as commemoration of individuals, focus on charismatic personalities, special patronage bodies, alumni associations, retrogressive bodies and hyperprogressive bodies.

Each of the dimensions mentioned brings out different aspects of the range and variety of international bodies. Several examples of organizations in any such group are cited to give a better grasp of the kinds of bodies which exist. Most of the named bodies are described in this volume, the number in parenthesis following each name being the reference number of the description. It should be stressed that a particular body could well exemplify several of the special characteristics discussed, although it may only have been cited because of the apparent dominant nature of a particular characteristic. The term "apparent" is deliberately used because the characteristic in question may not necessarily be of great importance in determining the actual functioning of the organization (eg the Howard League for Penal Reform could perhaps just as well be called the International League for Penal Reform).

It should also be stressed that in the main the dimensions and characteristics discussed attempt to draw attention to the many exceptional cases rather than to distinguish between organizations lacking any of the characteristics noted. It could be argued that there is a central core of international organizations which can only usefully be classified in terms of aims, internal structure, control, activities and membership. Unfortunately, it is these same bodies which tend to be multifunctional and therefore to be difficult to capture adequately and meaningfully in the schemes which have been proposed to date. Given the preponderance of organizations possessing characteristics distinguishing them, to a greater or lesser degree, from a model international organization, it is appropriate to attempt a descriptive review on this basis - in anticipation of a more adequate and comprehensive scheme.