Publisher Summary This chapter reviews the conceptual design of the cryogenic electrical feedboxes and the superconducting links of Large Hadron Collider (LHC). Powering the superconducting magnets of the LHC arcs and long straight sections is performed with more than 1,000 electrical terminals supplying currents ranging from 120 A to 13,000 A and distributed in 44 cryogenic electrical feedboxes (DFB). Where space in the LHC tunnel is sufficient, the magnets are powered by locally installed cryogenic electrical feedboxes. Where there is no space for a DFB, the current will be supplied to the magnets by superconducting links (DSL) connecting the DFBs to the magnets on distances varying from 76 m to 510 m. The complex task of powering the LHC superconducting magnets in the very limited underground available space will be performed with a combination of locally installed cryogenic electrical feedboxes and the use of superconducting links for the locations where the space limitations do not allow the installation of DFBs.