First fears about swinging turned out to be fine: it wasn't upsetting to watch her husband with another woman (it was actually great); neither spouse fell in love with someone new; and the marriage didn't suffer, but became stronger. They soon found house parties are happening out there, too, if you know where to look. Host couples get their homes kid-free by sending their kids out to sleepovers at a friend's house.

What is it about swinging that keeps happily married women in the lifestyle? One woman said swinging is all about being able to pleasure another woman. Another said it frees her to be her bisexual self. Everyone says it makes their marriage better. They explain they don't swing to fill a void in their marriage, but to enhance it.

Katherine, one thirtysomething wife, tries to explain the woman-to-woman attraction. "Women are soft, sensual, and usually very responsive. They are very concerned with what the experience is like for the other woman," she says. She also thinks the majority of women in the lifestyle and in the general population are either bisexual or bi-curious—it's just that women in the lifestyle are more willing to admit it and can explore their sexuality in a safe environment, with husbands there to witness and encourage things along. Does the idea of doing something extra "naughty"—the wild idea of a woman being with another woman—add to the excitement, too? Absolutely, Katherine says.

Most of these couples have even found best friends in the lifestyle. They socialize together, and it's not always sexual. They have dinner parties, celebrate birthdays, and help each other move. They consider lifestyle friends better friends than most "vanilla" (people not in the lifestyle) friends they have. "It's not all about the sex," several insist. But it sure sounds sexual.