  A future Higgs Factory will provide improved precision on measurements of
Higgs couplings beyond those obtained by the LHC, and will enable a broad range
of investigations across the fields of fundamental physics, including the
mechanism of electroweak symmetry breaking, the origin of the masses and mixing
of fundamental particles, the predominance of matter over antimatter, and the
nature of dark matter. Future colliders will measure Higgs couplings to a few
per cent, giving a window to beyond the Standard Model (BSM) physics in the
1-10 TeV range. In addition, they will make precise measurements of the Higgs
width, and characterize the Higgs self-coupling. This report details the work
of the EF01 and EF02 working groups for the Snowmass 2021 study.
