In Rules of Engagement, Elizabeth Moon brings together Esmay Suiza, the hero of Once a Hero, and Brun Meara, the reformed airhead heiress from the Herris Serrano books. Once a Hero was an unlikely mix of good military SF and tired psychological drama; Rules of Engagement is more of the same.

Fresh from her successes in the previous book, Lieutenant Suiza is sent to Command School. There she encounters Brun, the daughter of the highest official in the government of the Familias Regnant. Esmay has no time for a social life, and little patience with Brun's attempts to befriend her. Matters worsen when Esmay's erstwhile love interest, Ensign Barin Serrano, arrives at the school. When their acrimonious quarrel over Barin becomes public, Esmay is sent away in disgrace to a post on a deep space search-and-rescue crew, and a furious Brun runs away to tour her holdings in a private spaceship. Brun's recklessness propels her straight into danger at the hands of a misogynist militia group. Unfortunately, Esmay's too deep in disgrace to be allowed near the rescue effort, and it has already been demonstrated that the Regular Space Service can barely tie its collective shoes without her heroic assistance.

Readers with sensitive natures should be warned that Rules of Engagement includes brutal rape, murder, and egregious neo-Texas accents. (People who belong to groups with names like the "New Texas Godfearin' Militia" always have accents that make them sound like they have a wad of chewin' tobacco between gum and cheek, no matter how much time and space lies between them and their redneck roots.)

The action scenes are absorbing, and Esmay's stint as a junior officer in search-and-rescue is the best part of the novel. Unfortunately, the story falters whenever the focus shifts to the rather contrived personal melodrama that develops between Esmay, Brun, and Barin. These confident, decisive people behave like insecure teenagers when they're thrown together at Command School. Like Once a Hero, Rules of Engagement is at its weakest when it turns deeply touchy-feely, but at its worst it's no more irritating than the average episode of Star Trek: The Next Generation.

Through all the Familias Regnant books, Moon has threaded the issue of social problems caused by the rejuvenation process. An increasingly long-lived upper stratum in the military, political, and corporate worlds has caused an "age ceiling" that's stifling the younger generations of officers and personnel. In Rules of Engagement, Barin Serrano discovers that some recipients of the rejuv process are having mental lapses ranging from temporary forgetfulness to amnesiac paranoia. The consequences will presumably be dealt with in the sequel.

The story stands alone, but the surroundings don't. There's a great deal of character background from Once a Hero and the Herris Serrano books, and there are threads that remain to be tied up in the next book. If you're new to Moon's Familias Regnant universe, start with Once a Hero or Sporting Chance. If you liked Once a Hero, you'll enjoy this sequel. Unless you're an ardent fan, however, wait for the paperback.