A Delta Quadrant people at war with the Annari, whose disguised ship was commanded for a time by Harry Kim while carrying secret technology.
The Kraylor are a Delta Quadrant humanoid people locked in conflict with the Annari, who maintained a blockade around the Kraylor homeworld.
In Nightingale, Voyager came to the aid of a damaged Kraylor ship whose command crew had been killed. Harry Kim took command to see it home, believing the Kraylor's claim that it was a medical transport. He discovered that it was secretly carrying cloaking technology intended to help break the blockade. Kim still completed the mission, gaining hard lessons about command along the way.