  I review photo-polarimetric and spectropolarimetric observations of V838 Mon,
which revealed that it had an asymmetrical inner circumstellar envelope
following its 2nd photometric outburst. Electron scattering, modified by pre-
or post-scattering H absorption, is the polarizing mechanism in V838 Mon's
envelope. The simplest geometry implied by these observations is that of a
spheroidal shell, flattened by at least 10% and having a projected position
angle on the sky of $\sim37^{\circ}$. Analysis of V838 Mon's polarized flux
reveals that this electron scattering shell lies interior to the envelope
region in which H$\alpha$ and Ca II triplet emission originates. To date, none
of the theoretical models proposed for V838 Mon have demonstrated that they can
reproduce the evolution of V838 Mon's inner circumstellar environment, as
probed by spectropolarimetry.
