The Yearbook of International Organizations provides the most extensive coverage of non-profit international organizations currently available. Detailed profiles of international non-governmental (NGO) and intergovernmental organizations (IGO), collected and documented by the Union of International Associations, can be found here. In addition to the history, aims and activities of international organizations, with their events, publications, and contact details, the volumes of the Yearbook include networks between associations, biographies of key people involved and extensive statistical data.

Volume 1 (A and B) covers international organizations throughout the world, comprising their aims, activities and events. This includes names (in English, French and, where available, other languages), abbreviations and descriptions of over 34,000 not-for-profit organizations currently active in every field of human endeavor, as well as references to associated organizations, whose goals cross all economic, political and geographical borders, offering an insight into new, productive relationships.

Volume 1 also allows quick and easy cross-referencing from volumes 2, 3, 4, and 6.