The Cold Cash War is a 1977 science fiction novel by Robert Asprin. Based on an earlier short story of the same title, it is set in a dystopian future. In this future, corporations, referred to as Zaibatsu, have moved some aspects of their competition from the economic to the military.
The action takes place among mercenary soldiers. At times the conflict is under rules of engagement where "killsuits" are used. The killsuit is a reverse powered armor, acting to immobilize the soldier when the on-board computer decides that a lethal hit has been sustained. But sometimes the rules break down, and lethal weapons and violence are used.