More than 400 scientists, out of more than 1200 members of the Collaboration, participated in the meeting in person or remotely. The ET members discussed the status of the experiment, the technical challenges, the scientific case, and the scientific and technical progresses made by each of the ET boards. The ET Project Directorate presented the perspective from the funding agencies. Finally, the approved INFRA-DEV Horizon EU project, for supporting the preparation phase of the experiment, and the INFRA-TECH Horizon EU proposal, recently submitted to Brussels for supporting technological R&D activities, were introduced to the whole Collaboration.

During the meeting in Budapest, the ET Collaboration Board (CB) was constituted, chaired by Dr. H. Lueck, composed of the representatives from each of the 79 research units from 13 countries. During the first CB meeting, the ET Collaboration discussed the recently created ET bylaws that will govern the future of the experiment and initiated procedures to set up the required Collaboration committees. In addition, interim ET Spokesperson and Deputy Spokesperson figures were identified.

With the birth of the ET Collaboration, this symposium marks a milestone on the long journey of the Einstein Telescope endeavour.