How to ask...
I first brought up polyamory to my wife a couple years ago. It's an idea that she intellectually has no problems with, and sometimes finds intriguing. After much deliberation, yes/no conversations, she's decided that she's okay with me looking for an additional partner, and I feel the same about her.
There's a person I've pointed out as being interested, and my wife knows her by appearance. This person works at a local retailer, and whenever she's working, I try to go in her check-out line. We've had friendly conversation a couple of times, and what I think is flirting, but I'm not sure. I've always been bad at telling whether someone is interested, and I've had several bad experiences where I thought someone was, and it turns out they were not even remotely.
This person is somewhat of an alternative type by her appearance, so it's possible she might be open to a lifestyle like poly. My question is, how do I even bring up the possibility of going out? We'll never even get to know each other to know if this might be possible unless I can at least get that far. I have no contact with this person outside of her work, so I don't want to make it an awkward situation for her.