  We present a study of the magnetic field of the Small Magellanic Cloud (SMC),
carried out using radio Faraday rotation and optical starlight polarization
data. Consistent negative rotation measures (RMs) across the SMC indicate that
the line-of-sight magnetic field is directed uniformly away from us with a
strength 0.19 +/- 0.06 microGauss. Applying the Chandrasekhar-Fermi method to
starlight polarization data yields an ordered magnetic field in the plane of
the sky of strength 1.6 +/- 0.4 microGauss oriented at a position angle 4 +/-
12 degs, measured counter-clockwise from the great circle on the sky joining
the SMC to the Large Magellanic Cloud (LMC). We construct a three-dimensional
magnetic field model of the SMC, under the assumption that the RMs and
starlight polarization probe the same underlying large-scale field. The vector
defining the overall orientation of the SMC magnetic field shows a potential
alignment with the vector joining the center of the SMC to the center of the
LMC, suggesting the possibility of a "pan-Magellanic'' magnetic field. A
cosmic-ray driven dynamo is the most viable explanation of the observed field
geometry, but has difficulties accounting for the observed uni-directional
field lines. A study of Faraday rotation through the Magellanic Bridge is
needed to further test the pan-Magellanic field hypothesis.
