The City Who Fought by Anne McCaffrey & S.M. Stirling, Hardcover 1993
 
Simeon was a shell-person - the brain who ran Space Station SSS-900, on the fringes of human space. But things hadn't been going too well lately, and he was more than a little discontented. Though normally he enjoyed his work, these days it seemed boring. To make matters worse, his long-time parner had just retired and he was having a hard time adjusting to his newly assigned brawn - a strong-willed woman named Channa Hap, who seemed to feel it her duty to keep him in line.

Simeon's love of wargaming would find unexpected uses when the brutal Kolnari attack the nearby colony planet, Bethel. Sheltering the colony's refugee's brought "the city" an invitation to serious trouble with Kolnari pirates
 
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