CP Violating Effects in $e^{+}{e}^{-}\to ZH$ and Their Optimization

We consider the possibilities of testing CP conservation in the process $e^{+}{e}^{-}\to ZH$. The easiest is to measure the forward-backward asymmetry of the $Z$ boson, a nonzero value of which signals CP violation. The effects of CP violation are predicted in the two Higgs doublet model. We show here that a choise of optimal observables can improve the possibility of observing CP violation. Although the number of events is not large, useful information about CP violating parameters can be extracted.