Whispering your fantasy in your partner's ear can be really sexy, and it can be something that you would never even considering trying to do in real life. In fact, the "listener" should always be able to ask (later on) if the descriptions were something that were a suggestion in any way....I agree Ian, what is fun about the fantasy is it can be really wild, and something that would never reach the light of day (and if it did, might go not go "as planned" because in the fantasy it is so precisely choreographed)!

When working with my clients, I suggest that partners create a fantasy together. Often this is best done when they're hanging out, rather than when they're getting it on. Although, the activity does tend to lead to exciting sack sessions.

This way each person can share what turns them on, gauge how their partner reacts...and then add it to the mix, or ditch it for something else they're both into. This makes for a safe process that encourages both partners to be involved, is less intimidating and organic.

One thing that is so nice about sexuality is that it's a realm where you can push boundaries. I love the idea of putting fantasies out there with a willing partner and seeing where it goes. It's always a good idea to experiment with desires and fantasies solo before plunging in with a partner.

Some great great questions to ask a partner to gauge their fantasy realm are: "What are your fantasies?" "What do you think about when you masturbate?" "What kind of porn do you watch?"

One way to "share" fantasy is to have it start with both of you there. I sometimes recommend reading a book of sexual fantasies together. You can read together or take turns reading one to each other and then give a thunmbs up or thumbs down to how much it appeals to you. This often leads to a bit of incorporation of new things in bed that in fantasy are exciting to both of you. Watching erotica together can have a similiar effect. Go for either a very sexy regular movie or softer erotica because it tends to appeal more to both the woman and the man.

I also think that building trust in the relationship outside of the bedroom can open things up inside. One of the first role playing fantasies my husband and I had together came about very organically -- but I remember being so nervous when I took it up a level: would he laugh at me? Ask me what the heck I was doing? The fact that in the rest of our lives he is very supportive and positive gave me the courage to go for it. And, thankfully, he went along with things just fine!

I also think it's important to have a sense of humor and not take things too seriously. It's okay to laugh (WITH, Folks, not AT) and say, "OMG -- was that totally ridiculous?" And the answer might be, "Um, Yes. So we know we don't need to try that again." But on the other hand the answer might be, "Oh yeah, and I can't wait to do it again..."

But what about when one person's fantasy is another person's nightmare? Kristen wrote a nice piece for FOX this week about "when two becomes three" and introducing the idea of a threesome. I know that many couples are intrigued by the idea of a threesome, although very often one partner (often the guy) is pushing the idea. I've worked with many couples in which one partner was pressured to turn fantasy into reality and it severely damaged the relationship. Sometimes the "talking about" a fantasy can be arousing enough for both partner, but not always. Is it a matter of gradually introducing the fantasy and taking small steps. Is part of the problem that fantasies are often so raw and primal in their unfiltered form that we can't help but be shocked and scared? Is it a matter of dipping a toe in the shallow end before diving deep?

I agree that engaging in fantasy should not be taken to the extent that it may harm the relationship. However, often engaging in fantasy is a great way to spice up a relationship or perhaps add an element of excitement that wasn't a part of the relationship prior to the fantasy.

An important point in my FOX article about approaching a partner about a threesome is exactly what Paul mentioned - if your partner isn't interested - drop it. There is a lot to be said for enjoying a fantasy as just that...a fantasy! It can do wonders for the libido and level of spark in a relationship.

Do you think people should try to venture out of their comfort-zone?

I agree Shelley - I think people should venture out to a certain point. If it is detracting from the satisfaction of the encounter or if one person is to the point of feeling uncomfortable, I think its important to speak up and back up.