Romana II . . . was featured in a number of audio plays with former Doctor companion Leela (played by Louise Jameson) under the umbrella title of GALLIFREY.
Romana and Leela, on Gallifrey, kicking ass and taking names.
...um, yes please, I WILL HAVE SOME OF THAT.
Ward also did an audio spin-off with John "K9" Leeson about E-Space, but due to odd licensing situations they couldn't actually call it that, or call Ward "Romana." So her character was known as "The Mistress," and I am so not touching that one, not even to say it would've been really amusing if Leela had been in *that* audiodrama, too. (oops.)
(I learned about this from browing both Romana's and Lalla Ward's Wikipedia entries, where I also learned that Ward is married to Richard Dawkins -- yes, that Richard Dawkins -- to whose books she contributes illustrations. The two of them met at Douglas Adams's birthday party, at which "according to Adams they were the only guests who turned up on time and hence were obliged to speak to each other." They got married later that year. Well, Ward knew Adams because they worked on DR WHO together, but how the heck did Adams and Dawkins ever meet up? Simple: they became acquainted after *Dawkins wrote Adams a fan letter.*
Reason #5,412 why fandom is great: because you can write Douglas Adams a fan letter and as a direct result wind up getting married to Lalla Ward. Of course, being an eminent evolutionary biologist doesn't hurt.)