\label{fig:HiggsCross} The Higgs boson production cross section as a function of the centre-of-mass energy in unpolarized $\epem$ collisions, as predicted by the {\tt HZHA} program~\cite{cite:HZHA}. The thick red curve shows the cross section expected from the Higgs-strahlung process $\epemto {\rm HZ}$, and the thin red curve shows the fraction corresponding to the ${\rm Z}\to \nu\bar\nu$ decays. The blue and pink curves stand for the WW and ZZ fusion processes (hence leading to the ${\rm H}\nu_{\rm e}\bar\nu_{\rm e}$ and ${\rm H}\epem$ final states), including their interference with the Higgs-strahlung process. The green curve displays the total production cross section. The dashed vertical lines indicate the centre-of-mass energies at which TLEP is expected to run for five years each, $\sqrt{s} = 240$ GeV and $\sqrt{s} \sim 2m_{\rm top}$.