Wives having sex with other men, with their husbands' permission? When I first encountered this phenomenon around three years ago, I thought this was a rare fetish — a fascinating one, but unlikely to ever be widely practiced or acknowledged. The social and evolutionary programming just seems too strong, suppressing female and encouraging mate-guarding by males.

When I started to dig, I was surprised to find that wife-sharing actually had a very long history, though it was never mainstream. When it occurred, it was in unique economic and social circumstances. In fact, a number of the men and couples who practice this lifestyle told me that they find the rarity of it, and the taboo nature behind it, a big part of the thrill.

But, since my book Insatiable Wives came out, this sexual lifestyle, called hotwifing or cuckoldry, has gotten increasing recognition in the mainstream press. Here are just a few of these stories:

In the Dear Abby column of this week, a newlywed wife wrote to Abby, telling about how her husband enjoys her telling stories about her past sexual adventures and has even encouraged her to reconnect with an old boyfriend and enjoy herself. The young wife described that his suggestions left her "hurt and somewhat uncomfortable." Her husband suggested further that a "new story" would be a great addition to their sex life, but the young wife said she "wasn't sure."

Dear Abby challenged the wife, suggesting that she question whether she would be okay with her husband hooking up with an old girlfriend (though I'm not sure this is a valid issue — most of the men I interviewed in this lifestyle were happy with for themselves, just not their wives). Abby ended up recommending the wife resist this push, and that she could end up feeling "used and degraded" if she didn't. A funny thing is that in my book, I actually wondered if Dear Abby would ever print a letter like this, in contrast to the letters Dan Savage gets on a weekly basis. Guess that shows me!

Believe it or not, one of the unplumbed depths (sorry, no pun intended) of the Tiger Woods controversy contained a piece of this story. In an alleged email to one of his mistresses, Tiger wrote to her that he dreamed of being married to her, and coming home finding her sandwiched between actor David Boreanaz and Derek Jeter. Tiger described to her that he thought she would love it, if this actually happened.

This piece of the story got little , but I think it is fascinating, as who would ever look at successful, rich Tiger Woods and think that he would explore a cuckolding fetish? Just goes to show the depths of this phenomenon, still to be understood.

The story of Senator John Ensign, Nevada philandering conservative, also touches on this story. Ensign was having an affair with one of his female staffers and later paid off her husband, with money and a cushy lobbyist job, to keep her husband quiet. Little has been written about the woman's husband and his motivations, but I am sure am curious. At what point did he know about the affair, and when did he decide to get out of it what he could?

The story reminds me of some historical events in my book. In Somerset, England, a somewhat common practice was for husbands to encourage their wives to seduce another man, who they would then sue or blackmail, under laws that prohibit men from having sex with married women. In another story, an English Lord was appointed Lord of the Bedchamber to George IV, and stood by as his King had sex with the Lord's wife, Lady Elizabeth Melbourne.

Finally, in Florida a couple of years ago, a public official lost his job when it became public knowledge that his wife was a "mature" star, with his support and awareness.

What does all this mean? Well, it seems like the tip of an iceberg to me. If these stories are coming to the press in mainstream media, how much is happening that isn't making into the news? How much of this is truly going on? Is it happening more than it did in the past, and if so, why? Is this a good thing, representing female sexual independence, or a bad thing, representing females being "used and degraded?"