After the exploitation of the physics potential of the LHC pp collider in CERN, the high energy physics community is discussing the future research trend and the possible associated accelerators. The different programs take into account the exploration of the high energy frontier with very large accelerator complex or the precision domain thanks to the operation of very high luminosity colliders. In all these scenarios the lepton machines play a fundamental role thanks to the unique characteristics of electron positron collision in produce low background events. To allow these machines to reach the required energy and luminosity parameters the whole community is developing technology and design that find immediately applications also on low energy radiation sources.
We will give a general overview of the different future possible projects highlighting their specificities and characteristics. The associated technology and design developments will be also illustrated associated to the possible utilizations.