A preliminary investigation in 1971 by the Union of International Associations, led by Anthony Judge, showed that there was very little in the way of systematic descriptive listing of world problems. This prompted the UIA to undertake a data-collection exercise using the resources of the vast network of international organizations profiled in its Yearbook of International Organizations.
This long-term project was initiated in 1972 in collaboration with the foundation Mankind 2000. At the time it was judged to be an "impossible project", but the first work based on this research was published in 1976 under the title Yearbook of World Problems and Human Potential.
The UIA also had activities prior to 1939 which illustrate its long-term interest in relation to the Encyclopedia project. These include publication of the Annuaire de la Vie Internationale (1908-1909 & 1910-1911) which included information on problems with which international organizations were concerned at that time. Also published was a Code des Voeux Internationaux; codification générale des voeux et résolutions des organismes internationaux (1923) which listed those portions of the texts of international organization resolutions which covered substantive matters, including what are now regarded as world problems and what amount to plans or strategies for their solution.
Paul Otlet, co-founder of the UIA, also produced in 1916 a book entitled Les Problèmes Internationaux et la Guerre which identified many problems giving rise to and caused by war. In 1935 he attempted a synthesis, Monde: essaie d'universalisme -- connaissance du monde; sentiment du monde; action organisée et plan du monde, which touched upon many problems and their solution within a society in transformation. The preface bore the title The Problem of Problems, a topic he had first explored in 1918.