In 1986 the four societies GAMM, IMA, SIAM and SMAI decided to organize large International Conferences on Industrial and Applied Mathematics (ICIAM) every four years. To fulfill that aim, they created the so-called Standing Committee of the ICIAM. The first of those conferences took place in Paris in 1987 (see these SIAM News articles from May 1987 and September 1987), and the next ones, in Washington D.C (1991), Hamburg (1995) and Edinburgh (1999). In the meantime, in 1990 the Standing Committee decided to become a more formal entity, with formal members, and they created the CICIAM (Committee for the International Congresses on Industrial and Applied Mathematics). Note that the conferences became congresses from 1991 on.
The CICIAM had a chair, but no formal president, secretary or a treasurer either. The organization was very much linked to that of the coming or the past congresses. More societies became members little by little. And in 1999, the CICIAM decided to become ICIAM (International Council for Industrial and Applied Mathematics) and to start other activities apart from the pure organization of the congresses. At the same time, ICIAM was to have a president, a secretary and a treasurer. Later, the officers-at-large were added to the set of officers of ICIAM.
