The Festival de Théorie (Theory Festival) is an international scientific research forum set up in 2001 under the leadership of Jean Jacquinot, the current Scientific Adviser to the ITER Director General, who has supported the initiative ever since. It takes place every two years in Aix-en-Provence in the south of France during the month of July. The 2019 festival marks the event’s tenth anniversary and will be held over a four week period from 1 to 26 July. As in previous years, the first two weeks of the conference will be devoted to presenting the latest interdisciplinary results of research into magnetic confinement fusion, astrophysics and geophysics, as well as training courses for young researchers. During the last two weeks, this group of specially selected, talented young researchers will launch new research projects under the guidance of senior experts in the field.