Word files saved as Word Perfect

I visited a new eye doctor and he's interested in discussing transcription with voice files. I need to first ask him if he uses Word or Word Perfect so I don't know yet. I just wanted to be prepared in case he does use Word Perfect and if there's any chance I could do the work for him. I use MS Word now for another client and I don't know if I could switch back and forth between the two. It might get too confusing.

Thanks for your advice about the converter. If he does use Word Perfect there's a chance I could still do his transcription then.

Thank you.