Thanks everyone. I used the N key to open the companion window and was able to summon her back to my side.

My character is a Jedi knight currently questing through Coruscant. I'm going through Justicar territory and have run into a problem. I just completed a quest, the name of which I cannot remember, and my companion Kira has disappeared and I have no way of summoning her back. It happened after I discovered the missing doctors and learned that Tarniss is holding up in the ruins of the Jedi Temple. I sat through the scene where Kira used the computer to find Tarniss and said "Let's go", but when it cut back to gameplay, she was gone and her companion portrait was gone too. Is this supposed to happen, or is it some kind of glitch? I logged out and back on again, but she was still gone. Any info would be appreciated.