  We summarize recent attempts to unravel the role of plasma kinetic effects in
radiation mediated shocks. Such shocks form in all strong stellar explosions
and are responsible for the early electromagnetic emission released from these
events. A key issue that has been overlooked in all previous works is the
nature of the coupling between the charged leptons, that mediate the radiation
force, and the ions, which are the dominant carriers of the shock energy. Our
preliminary investigation indicates that in the case of relativistic shocks, as
well as Newtonian shocks in multi-ion plasma, this coupling is driven by
either, transverse magnetic fields of a sufficiently magnetized upstream
medium, or plasma micro-turbulence if strong enough magnetic fields are absent.
We discuss the implications for the shock breakout signal, as well as abundance
evolution and kilonova emission in binary neutron star mergers.
