Abstract

A next-generation energy-frontier linear electron-positron collider has been proposed as a facility for enabling ultra-precise measurements of the Higgs boson and top quark, as well as for searching for beyond-Standard Model physics with reach in some channels well beyond that of the Large Hadron Collider. The International Linear Collider (ILC), with a baseline CM energy of 500 GeV, has been proposed for realisation as a worldwide project, hosted in Japan; the Compact Linear Collider (CLIC), targeting CM energies up to 3 TeV, is being designed by an international project team centred at CERN. The motivation for, and status of, the ILC and CLIC projects will be reviewed.