The relations between Unesco and the WFScW were part of the partnership between Unesco and Non Governmental Organizations, but it remained marginal among all other activities of the Science Department.
The agreement between Unesco and ICSU had been elaborated in July 1946, accepted by ICSU, voted by Unesco in its General Assembly of Paris, November 1946, and finally signed in December 1946. It served as a model to prepare the agreement between Unesco and the WFScW.
The text was ready to be signed by January 1947, but it was vetoed by the American State Department. Nevertheless, Needham had started to apply it, by giving the WFScW an address and an office in Unesco House. For six months, Joliot, Bernal and Needham had to campaign to convince the majority of the Unesco Executive Council to accept the agreement. Needham had to retire his first proposal. Official meetings took place between WFScW the Science Department and the American Delegation. Pierre Auger, the French representative, and Paulo Carneiro, the Brazilian representative, were the main supports to the agreement proposal. But the State Department did not depart from its hostility to the WFScW. Against the American representative, a second-hand agreement was adopted by the Executive Council in July 1947, giving the WFScW an "observer status", and not full partnership. WFScW had much less financial support. It was not associated to the elaboration of Unesco official documents, but only invited to participate to some meetings.
With this agreement, the WFScW participated to the panels on the social aspects of science in Paris and New York, October 1947, to expert meetings, and to the General Conferences. Crowther represented the WFScW for the Second Conference in Mexico, November 1947. Inversely, Frank Malina, from the Science Department, represented Unesco for the first General Assembly of the Federation in Prague, September 1948. Needham, excluded from the official British delegation, represented the WFScW for the Third Conference (Beirut, December 1948). Bonet-Maury was the delegate for the Fourth Conference (Paris, September 1949).
Finally, the WFScW was unable to be represented in Florence, June 1950, for the Fifth Conference.19 The American delegation obtained this time the suppression of the agreement between Unesco and the WFScW. Even if the USSR joined Unesco in 1954, a new agreement was only re-signed in 1965.
The Unesco main support gained by the WFScW was a 6-month mission given to Crowther in November 1947 by Needham to travel to North America. The official aim was to study the state of preparation of the UN Scientific Conference on the Conservation and the Utilization of resources, to be held in 1949. This conference was an American proposal, and organized by the UN Social and Economic Council. Unesco felt this conference as a bit of an intrusion into its own field of competency. Unofficially this mission was also to help the construction of the WFScW in North America. With this mission, Crowther represented the WFScW at the Mexico Conference, discussed with the Social and Economic Council to try to obtain an observer status, and met the American AScW and other scientists associations in the United States. To this exception, the WFScW never got the expected support from Unesco.
As it is known, the USSR attempted to establish an intellectual organization alternative to Unesco. But the Wroclaw Conference, August 1948, failed to maintain links between communist and progressive Western intellectuals. This conference was a double failure: neither Unesco nor the pro-soviet organization managed to maintain political diversity. Unesco was perceived more and more as dominated by the Americans, which effectively became the case in the early 1950s.