It's true: There are secrets lurking behind your guy's fly and we're not talking about that! Believe it or not, the seemingly simple choice your man makes when he stocks up on undershorts can tell you a ton about him — his inner workings, his emotional makeup, even his boyfriend potential. To supply you with this essential info, we consulted the experts and turned our penetrating X-ray gaze below the belt. Pay attention to our underwear expose and, the next time you travel down that treasure trail, you'll be able to uncover the (almost) naked truth about your man's deepest desires.

BRIEFS
There's a certain charm to a guy who's not in a huge hurry to grow up. The tighty-whities wearer is a simple hunk with a simple philosophy: If it isn't broken, why fix it? "These are the default option," says Jeff Stone, co-author of Chic Simple Men's Wardrobe (Knopf, 1998). "This guy isn't looking to be innovative because he's content, more or less, with the status quo."

Guys who prefer briefs are also endlessly adolescent — playing football on the weekends to have fun, not to fine-tune their bods. Another draw to these drawers: According to Stone, they offer a little more, um, support. That snug factor is a big plus during those aforementioned scrimmages, But ladies beware: Since the brief-lovin' lug may be loath to settle down and get serious at this moment, you may not be the only girl with the inside scoop on what he sports south of the border.

BOXERS
Admit it. There's something swoon-worthy about a steadfast stud who doesn't shun tradition. And a man who picks boxers, the most conservative Skivvy selection, is likely to be a solid long-term romantic investment, says Stone. It's also, he says, a subtle assertion of a guy's transition to manhood.

But don't worry that this grown-up undergarment choice means your stud's a dud. Today, these crisp cotton undies offer the most style variety-coming in zillions of playful patterns. The pragmatic purpose behind them? They offer the best buffer between an itchy wool suit or stiff pair of jeans and a guy's preciously sensitive privates. We love them for their mystery factor: Nothing gets our motors running more than imagining what lurks under a pair of loose, baggy boxers.

COMMANDO
The most renegade men opt to go alfresco down below. A free-balling fellow tends to defy convention — at all costs. And his antiestablishment attitude extends from his underwear elections to his choice in careers. Likely occupations: surf instructor, bass guitarist-anything that fits into the category of corporate rebel. He's a lone wolf (albeit one who may be on the prowl), and his cocky, carefree self-confidence can be seductive if encountered at the right time (i.e., on a tropical vacation, between boyfriends, or just trolling downtown for a frisky night). And on the occasions when you are in the mood to fall temporarily in lust, fear not-this guy will be at the ready. No undressing required.

BOXER BRIEFS
Whoever invented this hot-as-hell undie hybrid has our undying gratitude. Any guy who sports these short-shorts probably has multiple gym memberships (you have to possess a seriously buff set of gams to pull off these mid-thigh babies). First modeled by muscle-covered Adonis types like Antoniono Sabato Jr., the guy who picks these is striving to be a specimen of physical perfection.

Stone says they offer even more support for sportsmen than their predecessor, the basic brief, because they don't ride up on the leg — indicating that every boyish brief-wearer needs only a nudge to become a brawny boxer-brief babe. One warning: This guy's healthy ego requires a woman who is willing to go the extra mile to keep her man's attention firmly focused on her. Up for the challenge?

BIKINI
Once favored only by sexually expressive Europeans and libidinous Latin lovers, this barely there underwear style is, according to Stone, gaining in popularity for the same reason more women are wearing thongs. "Clothes are just tighter now," he says. "Guys don't want panty lines either." True, "banana hammocks" don't leave much to the imagination, but so what? Chances are, you're looking to this bound- to-be-abed-hopper for a wild ride, and there's no need to waste time wondering... <<