  The discovery at the LHC of a scalar particle with properties that are so far
consistent with the SM Higgs boson is one of the most important advances in the
history of particle physics. The challenge of future collider experiments is to
determine whether its couplings will show deviations from the SM Higgs, as this
would indicate new physics at the TeV scale, and also to probe the flavor
structure of the Yukawa couplings. As a benchmark alternative to the SM Higgs,
we consider a generic two Higgs doublet model (2HDM) and analyze the precision
to which the LHC14, an ILC250, 500, 1000 GeV and a 125 GeV Muon Collider (MC)
can determine the gauge and Yukawa couplings. We allow for correlations among
the couplings. We include the impact of a Higgs total width measurement,
indirectly at the LHC and ILC and by a direct scan at the MC. We also discuss
pattern relations among the couplings that can test for singlet or doublet
Higgs extensions of 2HDMs.
