  We present a brief summary of asphericity effects in thermonuclear and core
collapse supernovae (SN), and how to distinguish the underlying physics by
their observable signatures. Electron scattering is the dominant process to
produce polarization which is one of the main diagnostical tools. Asphericities
result in a directional dependence of the luminosity which has direct
implications for the use of SNe in cosmology. For core collapse SNe, the
current observations and their interpretations suggest that the explosion
mechanism itself is highly aspherical with a well defined axis and, typically,
axis ratios of 2 to 3. Asymmetric density/chemical distributions and off-center
energy depositions have been identified as crucial for the interpretation of
the polarization $P$. For thermonuclear SNe, polarization turned out to be an
order of magnitude smaller strongly supporting rather spherical, radially
stratified envelopes. Nevertheless, asymmetries have been recognized as
important signatures to probe A) for the signatures of the progenitor system,
B) the global asymmetry with well defined axis, likely to be caused by rotation
of an accreting white dwarf or merging WDs, and C) possible remains of the
deflagration pattern.
