However, from 1920 to 1929, the Assembly met in Geneva at the Salle de la Réformation (in a building at the corner of Boulevard Helvétique and Rue du Rhône), then from 1930 to 1936 at the Bâtiment électoral or Palais Électoral (Rue du Général-Dufour 24, later used by the Red Cross affiliated International Prisoners-of-War Agency).

For special sessions, the Assembly met at the Pavillon du désarmement adjacent to the Palais Wilson.

It should be designed in such a way as to allow these organs to work, to preside and to hold discussions, independently and easily in the calm atmosphere which should prevail when dealing with problems of an international dimension.A jury of nine architects was selected to choose a final design from among 377 entries: Hendrik Petrus Berlage, Victor Horta, Josef Hoffman, Charles Lemaresquier, John James Burnet, Attilio Muggia, Ivar Tengbom, Carlos Gato of Madrid, and Karl Moser.

[5] Ultimately, the five architects behind the leading entries were chosen to collaborate on a final design: Julien Flegenheimer of Switzerland, Camille Lefèvre and Henri-Paul Nénot of France, Carlo Broggi of Italy and József Vágó of Hungary.

A medal showing the Palace of Nations with the Jura Mountains in the background was struck in silvered bronze.