How to implement all HL-LHC upgrades

The luminosity upgrade will require major changes in the LHC machine layout : about 1.2 km of the machine will undergo major renova tion or modification. In the paper we will review the list of main equipment foreseen to be replaced or to be added. We will review the upgrade plan that should start already in the Long Shutdown (LS) 2 (with the installation of the first dispersion suppressor 11T dipole – collimator unit , the superconducting link in Point 7 and the cryo-plant in Point 4), through to the major works in LS3, synchronized with an upgrade of the LHC detectors. Best estimates of the required duration of the various shutdowns will be discussed, and also the main risks and their mitigation