The 3rd edition of the Tritium School is a hybrid event taking place from 18 to 22 March 2024, in Marseille, France. It will consist of five days: four days will be dedicated to invited lectures and contributed talks, and the last day of the event a visit of ITER will be organised. The young generation of researchers working in fusion and fission research and development are encouraged to participate to gain knowledge and present challenges in the field of tritium management in fusion and fission facilities.