The ICMs are the largest mathematical conferences worldwide. They cover all areas of mathematics and are held once every four years. IMU decides the location of the ICM and assists the organization of the International Congress of Mathematicians. The first ICM took place in Zurich, Switzerland in 1997. Further information about the ICM can be found here.
The International Mathematical Union, in cooperation with other mathematical organizations and the local Organizing Committee of an ICM, provide Travel Support Programs for Mathematicians from developing and economically disadvantaged countries to enable them to participate at the ICM. At each ICM, the local organizers usually offer further grant programs.
Here you can find further information about the Travel Support Program for the ICM 2018: Open Arms Program.