I'm not directly experienced with this (most of my work is internal) so I don't know exactly how it works, or if they use Skype explicitly, but my company makes

I'm not directly experienced with this (most of my work is internal) so I don't know exactly how it works, or if they use Skype explicitly, but my company makes quite a few calls with other organizations. At worst, it would be possible using our Skype meetings and phoning any external orgs in using the dial-in phone line. Not exactly elegant, but functional. (Hopefully that's not what they do, though...)