International Union of Theoretical and Applied Mechanics

The International Union for Theoretical and Applied Mechanics (IUTAM) is an affiliation of about 500 mechanicians in about 50 countries, and involving about 20 associated organizations, including the International Council for Science (ICSU). The proceedings of symposia organized by IUTAM are published as "Procedia IUTAM".
The IUTAM was organized in 1946 at the sixth International Congress of Applied Mechanics in Paris. The ICAM first met in 1924 at Delft, Netherlands, under the guidance of Jan Burgers, with 214 participants from 21 countries.
The spirit of international cooperation was initiated by Theodore and Josephine de Karman, natives of Hungary that worked in Germany before going to Caltech. In fact, the "zeroth" International Congress of Mechanics was organized for 1922 to discuss hydrodynamics and aerodynamics:
Revival of internationalism after Hitler was described as follows:
IUTAM awards the Batchelor Prize for outstanding research in fluid dynamics every four years at the ICTAM conference. Named in honour of George Batchelor, the Australian applied mathematician and fluid dynamicist, the prize has a value of $25,000.