Cordelia's Honor (Vorkosigan Omnibus, #1)

This a previously-published edition of ISBN 9780671578282, newer one here.

In her first trial by fire, Cordelia Naismith captained a throwaway ship of the Betan Expeditionary Force on a mission to destroy an enemy armada. Discovering deception within deception, treachery within treachery, she was forced into a separate peace with her chief opponent, Lord Aral Vorkosigan - he who was called "The Butcher of Komarr" - and would consequently become an outcast on her own planet and the Lady Vorkosigan on his.

Sick of combat and betrayal, she was ready to settle down to a quiet life, interrupted only by the occasional ceremonial appearances required of the Lady Vorkosigan. But when the Emperor died, Aral suddenly became guardian of the infant heir to the imperial throne of Barrayar - and the target of high-tech assassins in a dynastic civil war that was reminiscent of earth's Middle Ages, but fought with up-to-the minute biowar technology. Neither Aral nor Cordelia guessed the part that their cell-damaged unborn son would play in Barrayar's bloody legacy. This edition includes an author's afterword, and a chronology of the events in the Vorkosigan Saga series. Cover art by Gary Ruddell.