  We investigate what can be learned at a linear collider about the sector of
electroweak symmetry breaking from a precise measurement of the Higgs boson
production cross section through the process e+e- -> hZ. We focus on deviations
from the Standard Model arising in its minimal supersymmetric extension. The
analysis is performed within two realistic future scenarios, taking into
account all prospective experimental errors on supersymmetric particle masses
as well as uncertainties from unknown higher order corrections. We find that
information on tan beta and M_A could be obtained from a cross section
measurement with a precision of 0.5 - 1 %. Alternatively, information could be
obtained on the gaugino mass parameters M_2 and mu if they are relatively
small, M_2, mu approximately 200 GeV.
