Vienna Salvatori was a human interstellar bounty hunter.
Vienna was once tasked with capturing the Seventh Doctor and Kylo Sorsha by the Wrath Justice League. She met the Doctor a couple of times, the first time she met him was the second time he met her, and she wanted to know how he knew the future. She disabled Kylo's security monitors to allow the Wrath to find him. (AUDIO: The Shadow Heart)
Vienna was hired by Cage Zorn on Mars to find Lara Memphis after she stole Kronos Vad's book from Cage. She wondered why she was employed to find her but not kill her. On that occasion, she encountered Bernice Summerfield. (AUDIO: The Lady from Callisto Rhys) She helped Benny recover from an accident and then came with her to The Archive to give the Kronos Vad book back. (AUDIO: The Phantom Wreck)
Behind the scenes Edit
A series for this character was announced before her first story had even been released. Producer David Richardson was quick to clarify that he "did not see it as a Doctor Who spin-off. It's its own thing. It's not set in the Doctor Who world at all." However, with the release of the third series of Vienna in 2016, Big Finish released a promotional article on their website that compared the Vienna series to various Doctor Who spin-offs such as Gallifrey, Charlotte Pollard, Jago & Litefoot, and Counter-Measures. Moreover, in a behind-the-scenes interview included with the 2018 release Vienna: Retribution, Chase Masterson herself referred to Vienna as being a Doctor Who spin-off. 
In 2015, Vienna once again crossed over into the DWU in The Worlds of Big Finish, the story of which involved Bernice Summerfield, Iris Wildthyme, Abby, and Zara. Big Finish Productions executive producer Nicholas Briggs, when answering a fan question inspired by The Worlds of Big Finish about the relation of other Big Finish ranges that had crossed over with Doctor Who related works, commented that "It's all fictional. Which fictional world it all belongs to is entirely up to [individual listeners] and we don't have a firm policy on it." (VOR 73)