The World Association of Theoretical and Computational Chemists (WATOC) is the leading organisation in that field.  WATOC organises a congress every three years and, at the most recent event in Munich last month, more than 1500 delegates from dozens of countries participated.  Peter Gill has served as the vice-president of WATOC since 2011 and, during the Closing Ceremony in Munich, he was installed as the president for a six-year term until 2023.