Komarr, by Lois McMasters Bujold

Having been confirmed by Emperor Gregor, and sworn in as Imperial Auditor in front of the Council of Counts, Miles goes offplanet to observe another auditor, Vorthys (an esteeemed engineering professor) in investigating the cause of a collision which has caused damage to the soletta array on Komarr. This array is essential to the cause of terraforming the planet, which appears to be Mars-like, from the descriptions. Komorrans have been living under domes on the planet for a century or so, and hope to be able to move to the surface without wearing breath masks sometime in the next millenium.

Auditors Vorthys and Vorkosigan set up shop in the home of Vorthys' niece, Ekaterin, and her husband Tien Vorsoisson. Tien is an administrator in one of the districts of the terraforming project. We get to learn quite a bit about the state of the project when we tag along with the auditors on a dog and pony show arranged by Tien and the people working with him, and later we get to go on a shopping expedition with Miles and Ekaterin and learn a bit more about life in Komarr.

As it turns out, Tien has been involved in a bit of shady business with the Komarran "resistance", accepting bribes out of funds embezzled from the terraforming project. Ekaterin discovers his part in this, and it's the last straw for her in an unhappy marriage. When she tells Tien she's leaving him, he panics and tries to get Miles to declare him an Imperial Witness (immune from prosecution) if he'll reveal the Komarran's plot. Miles and Tien pay a surprise visit at one of the terraforming stations, get surprised themselves, and Tien dies accidentally and stupidly. At this point, the plot threads begin to come together, and the damage to the soletta array appears to be a part of something larger and much more deadly.

What's perhaps more important, however, is that Miles falls hopelessly in love with Ekaterin Vorsoisson, even before her husband is dead, we get to watch him navigate the maze between his Vorish sense of propriety and his usual disregard for anything remotely resembling rules and utter lack of social inhibitions.

There's a great "in" joke here when Ekaterin offers to take Miles shopping, and he quips "That's not something one offers a son of my mother lightly" (paraphrase). There's also a marvelous moment near the end of the book when Miles absolutely knows he must have this woman as his wife, and she quizzes him about his ex-girlfriends. She drags it out of him that one of them has become an admiral of a mercenary fleet, another the head of a cryogenic clinic, another has become one of Cetaganda's Empresses, and she begins to realize that Miles is one of those rare people who encourage others to dream big and accomplish even bigger.

Just another great book in the plot and character development for Lord Auditor Miles Vorkosigan.