The problem with studying adultery, of course, is that cheating is shrouded in secrecy, and philanderers are no more eager to discuss their discretions with a researcher than they are with their spouses. Further complicating the issue is what exactly constitutes cheating in this day and age -- is it just sex? Emotional betrayal? A stolen kiss?
According to data from the American Association for Marriage and Family Therapy, about 15 percent of wives and 25 percent of husbands have had sex with someone who's not their spouse [source: Jayson]. When actions other than sex are considered, the numbers rise: Marriage counselor M. Gary Neuman claims one in 2.7 men will cheat at some point [source: CNN]. While we may not have exact numbers, it appears that men cheat more than women, but the ladies have been cheating more frequently in recent years [source: Bryner].
As for why men and women cheat, the conventional wisdom for years has been that men seek quantity and women seek quality; in other words, men will cheat to have more sex, and women will cheat because they seek an emotional quality that is missing in their marriage [source: Bryner]. More and more marriage counselors and psychologists are saying that women aren't the only ones who cheat because they seek intimacy and attention after they've been neglected by their spouses. According to M. Gary Neuman, 92 percent of cheating men say it's not about the sex, it's about feeling underappreciated. Furthermore, Neuman's work shows men don't cheat because they find someone more attractive than their spouse; 88 percent of the men claim the other woman wasn't better looking than their wives [source: CNN].
Of course, such results again highlight the problem of studying infidelity. Are men claiming emotional neglect because they know that's what a psychologist or marriage counselor would like to hear? It's possible that such a claim engenders more support and sympathy. And to some extent, it pins the blame on the wife who created such a neglectful situation. In 2008, Dr. Laura Schlessinger garnered headlines when she claimed that women were somewhat responsible for their husbands' affairs [source: Celizic]. It's a woman's job, according to Dr. Laura, to make a man feel like a successful superhero stud; anything short of that, and you can't blame a man's wandering eye.
But some other studies show that no matter how great a marriage is, men and women may find themselves in another's arms.