How do I show support for her fantasy?

Just tell her what you just told us

Wow you sound like a great guy. most dudes could not handle not being involved with two women. just talk to her about it and try to set something up you guys already do everything Else together you are obviously very sexually open so I don't see why it should be a problem

Be sure to tell her that if she feels like she wants to bring another woman into the bedroom, that you totally support her. Don't hide the fact that it would turn you on from her. Women like to hear that the things they do, or want to do, turn their husbands on. Be blunt with her, and tell her exactly what you're thinking. If you want to have another girl be a part of your sex life, don't be shy. Good luck!

Hmmm... I wouldnt push it. Its a fact that invisible support is better than obvious support. So when she says stuff about it, just tell her that you dont think its cheating and that if she wants to do something like that, to go for it, and that you dont need to be there. TELL HER I SAID GO FOR IT AND SHE WONT REGRET IT!

Just tell her what you have told us. Tell her that this is not only something that you want for her, but it is also something that you want for yourself. She needs to feel comfortable about talking about this with you. She needs to understand that this would be a good thing for both of you.

just tell her. she told you her fantasy just be honest and tell her yours. You seem to have a pretty open minded relationship you should be able to speak openly about what you like

wow, a married couple for one should never have thoughts like that... do not know really what to say to this... maybe join a porn group of some kind????

Next time you are out,start pointing out sexy women and see what she says.

do you mind if I fu*k your wife? i can bring my girlfriend and you'll watch. Come on man what the hell is wrong with you?

tell her you think it's hot and you want to tape it for later review.