  We review the production of scalar Higgs-like particles in high-energy
electron-electron collisions, via the fusion of electroweak gauge bosons. The
emphasis is on how to distinguish a CP-even from a CP-odd Higgs particle. Among
the more significant differences, we find that in the CP-odd case, the Higgs
spectrum is much harder, and the dependence of the total cross section on the
product of the polarizations of the two beams is much stronger, than in the
CP-even case. We also briefly discuss parity violation, and the production of
charged Higgs bosons.
