  The Standard Model global fit to precision data is excellent. The Minimal
Supersymmetric Standard Model can also fit the data well, though not as well as
the Standard Model. At best, supersymmetric contributions either decouple or
only slightly decrease the total chi^2, at the expense of decreasing the number
of degrees of freedom. In general, regions of parameter space with large
supersymmetric corrections from light superpartners are associated with poor
fits to the data. We contrast results of a simple (oblique) approximation with
full one-loop results, and show that for the most important observables the
non-oblique corrections can be larger than the oblique corrections, and must be
taken into account. We elucidate the regions of parameter space in both
gravity- and gauge-mediated models which are excluded. Significant regions of
parameter space are excluded, especially with positive supersymmetric mass
parameter mu. We give a complete listing of the bounds on all the superpartner
and Higgs boson masses. For either sign of mu, and for all supersymmetric
models considered, we set a lower limit on the mass of the lightest CP-even
Higgs scalar, mh > 78 GeV. Also, the first and second generation squark masses
are constrained to be above 280 (325) GeV in the supergravity (gauge-mediated)
model.
