  If several interventions performed on a quantum system are localized in
mutually space-like regions, they will be recorded as a sequence of ``quantum
jumps'' in one Lorentz frame, and as a different sequence of jumps in another
Lorentz frame. Conditions are specified that must be obeyed by the various
operators involved in the calculations so that these two different sequences
lead to the same observable results. These conditions are similar to the
equal-time commutation relations in quantum field theory. They are sufficient
to prevent superluminal signaling. (The derivation of these results does not
require most of the contents of the preceding article. What is needed is
briefly summarized here, so that the present article is essentially
self-contained.)
