Finding CP-violating Higgses

In a general two-Higgs-doublet model with CP violation in the Higgs sector, the three neutral physical Higgs bosons have no definite CP properties. A new sum rule relating Yukawa and Higgs-Z couplings implies that a neutral Higgs boson cannot escape detection at an e^+e^- collider if it is kinematically accessible in Z+Higgs, $b\bar b+$Higgs and $t\bar t+$Higgs production, irrespective of the mixing angles and the masses of the other neutral Higgs bosons. The implications of the sum rules for Higgs discovery at the Tevatron and LHC are briefly mentioned