  HL-LHC federates the efforts and R&D of a large international community
towards the ambitious HL- LHC objectives and contributes to establishing the
European Research Area (ERA) as a focal point of global research cooperation
and a leader in frontier knowledge and technologies. HL-LHC relies on strong
participation from various partners, in particular from leading US and Japanese
laboratories. This participation will be required for the execution of the
construction phase as a global project. In particular, the US LHC Accelerator
R&D Program (LARP) has developed some of the key technologies for the HL-LHC,
such as the large-aperture niobium-tin ($Nb_{3}Sn) quadrupoles and the crab
cavities. The proposed governance model is tailored accordingly and should pave
the way for the organization of the construction phase.
