Early studies of fatigue of material in the mid-19th century led to the development of fatigue design methods and, for example, to the definition of the fundamental concept of conventional fatigue limit. The number of cycles applied, particularly in experimental studies, was limited to tens of millions mainly for technical reasons and refered as  the High Cycle Fatigue domain (HCF). One century later, some researchers conducted studies to explore higher cycle numbers, up to a billion or more calle the Very High Cycle Fatigue domain (VHCF). These studies showed that the design methods used in the HCF field could not guarantee safety of the structures in the VHCF field. Furthermore, the physical mechanisms involved were different from those more commonly known in  the HCF domain. Since then, experimental techniques have developed and become more widespread, and more and more research teams around the world have focused their research on VHCF.

 In the 1990s, the VHCF conferences were created to bring this scientific community together. These are international events organized every three years, bringing together the scientific community working on very high cycle fatigue (VHCF). The first VHCF1 congress was held in 1998 at the CNAM in Paris. Since then, the VHCF congress has been organized by different countries on different continents:

• VHCF1, 1998, Paris - France;
• VHCF2, 2001, Vienna - Austria;
• VHCF3, 2004, Kusatsu - Japan;
• VHCF4, 2007, Ann Arbor - USA;
• VHCF5, 2011, Berlin - Germany;
• VHCF6, 2014, Chengdu - China;
• VHCF7, 2017, Dresden - Germany;
• VHCF8, 2021, Sapporo – Japan ;
• VHCF9, 2024, Lisbon – Portugal.

Twenty nine years after Claude Bathias organized the first VHCF congress at the CNAM in Paris, it is a pleasure for us to organize the next VHCF congress in Paris in April 2027 at the Parisian campus of the national high engineering school Arts et Métiers Institute of Technology (ENSAM).