WHEN IT COMES to the business of cheating, Noel Biderman is boss. His website AshleyMadison.com—named, he says, after the two most popular monikers for baby girls—functions like any other dating site, with profiles, searches, messages and photos. But at Biderman's site, the dating pool comes with baggage: namely girlfriends, boyfriends, wives and husbands.

"We offer a good, honest affair. Guaranteed," says site president and founder Biderman, a husband of seven years and father of two children. "We're no eHarmony, that's for sure."

What AshleyMadison is, Biderman says, is a place where people can go to fulfill the needs that aren't being met at home, a human buffet line where all the dishes know they'll never be the main course. Users and fans say it's a website that makes open what's happening in secret on dating sites already. Critics say it's an online cesspool that breeds infidelity—a 24/7 computerized home wrecking service that should be shut down for good.

Biderman says they just wish they'd thought of it first.

"We looked at data that showed 30 percent of the people on other dating sites were cheating or looking to cheat," says Biderman, speaking from his office in New York. "We thought to ourselves that all these people that are posing as single is risky. Why not come to a community where people can confess that they're looking to cheat and people get it? We're creating an honest community for cheating."

Biderman's "honest community" was launched in 2001 and now boasts more than 5.2 million users. A media-savvy seeker of controversy, the well-dressed, balding 38-year-old has braved the booing from audiences at The View and The Tyra Banks Show to plug his site and preach his "it's only sex" spiel. The cavalier gentlemen's-club approach translates to the online dynamic. On the site, women play mostly for free. Guys buy "credits" that are used for sending digital "gifts" to other users and accessing private data. Everyone creates a profile that lists a photo, some stats on appearance and a list of things they're into: spanking, threesomes, schoolgirl outfits or Polynesian albinos in football pads. A juicier collection of pics and stats are available when a user sends someone a "key" that provides access to his or her "private showcase."

"Brie," a 32-year-old wife of five years, says she joined because things just weren't working out at home.

"To me it was either this or get a divorce. And getting a divorce is more drastic," says the woman, who asked that her real name not be used. "I wanted an alpha male, someone who really gets it done. I don't think my husband suspects."

Brie says she met her current fling six months ago. Before that, her dalliances amounted to "kissing a few guys, but that's it." The man, she says, is older and married as well. Their dates typically consist of dinner and drinks followed by a motel room pit stop, then a long, occasionally guilt-ridden ride home to their spouses. "It can't go on forever," she admits. "It's fun while it lasts, though."

And the consequences? Carol Bass, a licensed marriage counselor in Santa Cruz, says more and more patients are coming in looking to overcome infidelity and put their marriages back on track. Sometimes it's possible to save the relationship, she says. Many times it's not. But it usually isn't the sex that ruins the union. It's the lying and deceit.

"When I'm working with a couple, quite frequently a person will say, 'I had an inclination that something was going on, but my partner continued to lie, saying that nothing was going on,'" Bass says. "At that point, they're not only damaging the relationship, they're distorting their partner's reality. And no one has the right to distort someone's reality."

Bass says she won't do couple's therapy with a couple in which one partner is cheating until the affair is broken off, though she says she will still work individually with a cheater. Biderman, meanwhile, insists that cheating itself can be a sort of marriage therapy and that American culture puts too much importance on monogamy, which he maintains is "against our DNA."

And as lovers nationwide stock up on chocolates and flowers for Valentines Day, adulterers on AshleyMadison will be stocking up on motel reservations and alibis for the day prior, a holiday Biderman heralds as "Mistress Day." Either way, it's hard to argue with the fact that philandering men and scandalous women have been around a lot longer than Biderman and AshleyMadison.com.

"There are millions of people that are suffering through a sexless marriage," Biderman says. "I say, don't go visit a prostitute, don't lie to someone else about whether you're married or not. If you need that sexual element, come to AshleyMadison, and you can get it."

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