We've gotten multiple clicks on some of our ads from the same ip addresses. The ip's in question appear to belong to a chinese proxy network. Think it's foul-play?

If so, what should we do about it?

Google should generally detect this - they're getting much better at click fraud (and it's in their interest to) so they're taking a much closer look at this kind of thing. If you have an AdWords rep, contact them about this.

You should report that to your advertising network. If you advertise on bigger network, they should have an automated fraud click prevention though.

The ip's in question appear to belong to a chinese proxy network.

Ban China as a source of traffic in Google Adwords? (assuming you're using Google Adwords)