  We study abrupt changes in the dynamics and/or steady state of fermionic
dissipative systems produced by small changes of the system parameters.
Specifically, we consider open fermionic systems whose dynamics is described by
master equations that are quadratic (and, under certain conditions, quartic) in
creation and annihilation operators. We analyze both phase transitions in
steady state, as well as "dynamical transitions". The latter are characterized
by abrupt changes in the rate at which the system asymptotically approaches the
steady state. We illustrate our general findings with relevant examples of
fermionic (and, equivalently, spin) systems, and show that they can be realized
in ion chains.
