  We report results bearing on the behavior of non-local decoherence and its
potential for being managed or even controlled. The decoherence process known
as entanglement sudden death (ESD) can drive prepared entanglement to zero at
the same time that local coherences and fidelity remain non-zero. For a generic
ESD-susceptible Bell superposition state, we provide rules restricting the
occurrence and timing of ESD, amounting to management tools over a continuous
variation of initial conditions. These depend on only three parameters: initial
purity, entanglement and excitation. Knowledge or control of initial phases is
not needed.
