If single women could effortlessly clue in to single men's myriad character deficits, we guys would never succeed at getting a second date. So unfortunately for you, we've gotten pretty good at concealing our personality blemishes. But I'll let you in on a little secret: There are ways to weed out the hopeless losers before you waste too much of your precious dating time -- or worse, get too attached. You just need to put your potential partner through a few simple tests that will slyly force him to reveal any unacceptable attributes. If you're lucky, the guy you're currently grooving on will pass with flying colors. And if he doesn't? Well, then you're justified in kicking him to the curb.

Any guy worth his testosterone supply will get a little jammed up when he encounters a rival for his woman's affection. But to find out if his possessiveness crosses over into psycho territory, set up a few jealousy-provoking scenarios and see if your dude handles himself like a man... or like a man in need of a restraining order.

For example, go to a crowded club and hit the dance floor. Be sure to expand your orbit so that it appears as if you're dancing with some of the random guys around you. A reasonably jealous type might shoot the other Y-chromosome owners dirty looks but stop short of shooting off his mouth. A sure sign that his jealousy is a liability: He starts rolling up his sleeves for some Sopranos-style action.

If the dancing-diva scenario seems too risky, you can try something more coquettish, like mild flirting. Keith, 25, admits to revealing his caveman tendencies accidentally in a case of mistaken flirtation. "I was out for coffee with a new girl, and she started chatting with an Australian guy at the table next to ours. I've always been the jealous type, so I was fighting the urge to say something. Finally, after 10 minutes of giggle-spotted small talk, I snarled, 'I'm sorry, but she's on a date with me!' and led her out of the restaurant. On the sidewalk, she told me that she'd spent a year in Australia and vowed to be as friendly to foreign tourists here as the Aussies had been to her. I came off looking like an insecure freak." A good rule of thumb: Like Keith, every guy deserves one or two jealousy flare-ups. If it happens more frequently than that, give him his walking papers.

Many men pride themselves on being frugal, believing that thriftiness is a money-management skill that takes years to hone. But there's a big difference between possessing the ability to save a few bucks and insisting on it at every turn. So unless you covet cubic zirconia, it would benefit you now to find out just how stingy your beau is. The quickest way to see where he falls on the cheapskate scale? Observe his tipping generosity. When he springs for dinner, does he throw down the standard 20 percent without hesitation, or does he try to explain that because his water glass wasn't refilled, he's deducting accordingly? David, 27, unwittingly flashed his frugal nature after a dinner date. "I paid, but she offered to cover the tip. She asked me how much she should leave, and I suggested five dollars, which was a little over 10 percent of the bill. She just glared at me, put $10 down on the table, and went to get her coat."

True, few guys will lunge at the chance to seal off their romantic options by getting into an exclusive relationship. But to find out if a man is resigned to never surrendering his bachelor status, you have to do some sleuthing. The best way? Expose him to commitment-phobe kryptonite: a couple in a serious relationship.

Arrange a dinner date with two of your friends who have just moved in together, bring him to your cousin's engagement party, or have him escort you to a wedding. Any of these occasions will give you the opportunity to observe casually, "They look so happy." Then read his response: sarcasm ("Yeah, but in six months, they'll have put on 30 pounds and stopped having sex"), skepticism ("Really? They seem a little bored to me"), or sappiness ("Maybe one day... ").

Another way to get clued in to his commitment potential is to go shopping with him and watch what he eyes and buys. Allan, 28, inadvertently exposed his frat-boy-forever credo when his new girlfriend took him to a junky antiques store. "I saw her flinch when I spent my last $25 on a beat-up dentist's chair for my living room. She said, 'You do realize that nobody but you could want that monstrosity in their house, right?' That was precisely the point -- I didn't see myself taking anyone else's decorating proclivities into consideration for a long time. Unfortunately, she got the message too."

When spreading their seed was vital to the survival of the human species, men had an excuse for wandering. And though most modern guys recognize that the perpetuation of the population doesn't depend on them alone, there are still a few who just can't seem to extinguish the urge to go through the motions. To find out if your man is one of the evolved, do this: The next time you're watching a TV show featuring a two-timer, drop a comment about how guys who cheat are greaseballs. If he hems and haws, clears his throat uncomfortably, or says something like, "Well, every situation is different," you may have a philanderer on your hands.

Since a really slick cheater, however, will know better than to spill his fidelity theories, it may be necessary to toss your guy into the deep end. Take him to the type of restaurant that tends to have an attractive waitresses. If you suspect he's more concerned with ogling the wait staff than with finding out how your day was, you may be dealing with a chronic swivel-head.

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