Would it be appropriate to ask my coworker to conduct her phone calls off of speaker phone?

My coworker and I share a common wall between our private offices. She conducts every single call on speaker phone. The wall is not sound-proof and is only a means of providing privacy between our offices. I think she believes that if she closes her office door then no one can hear her. She has been doing this more and more lately. This week is especially bad. Now she's even conducting personal calls on speaker phone. She has an expensive wireless headset that she doesn't use either. I would like to ask her to stop using speaker phone, but she's not the nicest person. In fact, she's rather mean spirited.

So, should I ask her?

And if you think I should ask her to stop, what should I say?

Definitely ask her to stop it. It's one of my big pet peaves. Just say that you need that to happen in order to be productive. If she's mean-spirited then there's no need to sugar coat it. She's going to probably have an impolite reaction anyway.

She should be using her wireless headset if she wants to be hands free. If you're not comfortable approaching her on this, have your boss, or manager talk with her. No names need to be mentioned-she just needs to know that it can be disruptive to other employees, plus sensitive information could be broadcast.

She probably doesn't know that you can hear her, and would be embarrassed if she did know. I would simply turn the tables and conduct a loud speaker phone conversation in my office. Once she hears your conversation through the wall maybe she'll stop her calls.

Definitely ask her. I'm sure she wouldn't hesitate to ask you, right?

Play the 'personal' card. Let her know - politely of course - that you have been able to hear her conversations, and were especially bothered by those of personal nature. Say "I'd really appreciate it you would keep your phone OFF of speaker, and I'm sure you don't want me hearing YOUR conversations either. I understand that speakerphone gives you free hands to do other things in the office, but these walls do not mask the sound, and its quite distracting."

I would simply ask her to turn the volume down or turn speaker off; remind her that you hear every word that is said and that might help.

Like you said, she might think that no one can hear her. You can simply say, "Hi Doris, I'm not sure if you're aware, but I can hear when you make calls in your office, even when you have the door closed. I just wanted to let you know because I can hear the whole conversation. Sometimes I find it distracting." This should hopefully be enough.