Thanks for the tips.
I'll have to try being less secretive about the arrangement my wife and I have. My biggest fear is that when people find out about our openess, I'll be somewhat embarrassed by the fact that my wife finds a lot more partners than I do. It sounds great on paper, but in reality it's a bit different.
When I do tell people about our arrangement, I'll make sure the one that do find out are both open minded and discrete.
Yes, I am a bit uneasy about the whole "don't get your honey where you get your money", but aside from "dating" sites which don't seem to work, I don't have many opportunities to meet potential partners. Still I'll make sure that I keep my friendship with the new girl in the office at just that. If I do meet someone at work I'll make sure they at least work in another department.