The International Congresses of Mathematicians (the ICMs) are among the largest mathematical conferences worldwide. They cover all areas of mathematics and are held, as a rule, once every four years. The first ICM took place in Zurich, Switzerland in 1897. The International Mathematical Union (IMU) considers the organization of the ICMs as one of its most important activities.

An ICM is a showcase of what is going on in contemporary mathematics in the world at the time when it takes place.  Outstanding mathematicians from different regions of the world present the best work covering all mathematical subfields. The ICMs, thus, point to the future of mathematics.

The structure of the ICM is determined by the ICM Structure Committee, and the speakers at the Congress are carefully selected by a Program Committee that is supported by section panels. The speakers are mathematicians of the highest reputation, who present current trends of research to a broad mathematical audience.

The scientific prizes awarded by IMU are considered to be the highest distinctions in the mathematical world. They are presented in the Opening Ceremony of an ICM: The Fields Medal (two to four medals are given), the IMU Abacus Medal[1], the Carl Friedrich Gauss Prize, and the Chern Medal Award. At the Closing Ceremony of the ICM, the Leelavati Prize, sponsored by Infosys, for excellence in mathematical outreach is awarded.

Prior to the ICM, the IMU hosts a two-day meeting of its General Assembly (GA), which is the governing body of the IMU. The initiative to host an ICM comes from the Adhering Organizations of the IMU.

1Previously the Rolf Nevanlinna Prize