The investigation of the internal microstructure of materials in 3D as well as the dynamical processes occurring in them is a very active direction of research. Possible applications are found in the fields of material science, biomedicine, paleontology, cultural heritage, etc.

Nowadays, synchrotron X‐ray imaging is one of the most used techniques for this purpose. In recent years different beamlines in Europe have focused their developments towards 4D imaging techniques (combined with in situ approaches) with the objective of achieving a new technique, "real time tomography", which combines 3D spatial resolutions of few microns and temporal resolutions below the second. The beamline FAXTOR, currently under pre-design stage, aims at representing in the future an important reference in the field of 4D tomography. During this workshop the required technical specifications of FAXTOR will be presented and discussed.