Oxygen plays a vital role in radiation therapy, since it's the most well-known radiation sensitizer. Increased tissue oxygen has been shown to reduce the protective nature of FLASH in healthy tissue. The FLASH workshop will allow for an open discussion of the ideas of how oxygen impacts FLASH-RT. This event is aimed at medical physicists, biologists, clinicians, bioengineers and students in the respective fields. You are welcome to submit your abstract for presentation during this workshop. Only participation in person is possible. Registration start: Februar 12th 2024. Registration deadline: June 1st 2024. Further information: www.dkfz.de/flash_workshop2024.