  The decay $K_L\rightarrow \pi^o\nu\overline{\nu}$ is an excellent probe of
the nature of CP violation. It is almost entirely CP-violating, and hadronic
uncertainties are negligible. Experiments which hope to detect the decay are
currently being planned. We calculate the decay rate in several extensions of
the standard model Higgs sector, including the Liu-Wolfenstein two-doublet
model of spontaneous CP-violation and the Weinberg three-doublet model. In a
model with an extra doublet, with CP-violation arising from the CKM sector, the
rate can increase by up to 50\%. However, in models in which the CP violation
arises either entirely or predominantly from the Higgs sector, we find that the
decay rate is much smaller than that of the standard model, unless parameters
of the model are fine-tuned.
