Think of fashion like the stock market: It's all a matter of risk versus reward. And this year it was Hollywood's men—sticking with blue-chip performers such as the classic suits favored by Prince William and George Clooney—who were the big winners. Still, no one can blame the women for wanting in on the millenium's hot opportunities: plunging backs and necklines, belly-baring hip-huggers, leopard prints, leather, fluttery ruffles, stiletto-heeled boots, and did we mention color? Fashion's savviest, including Heather Locklear and Jennifer Aniston, got exciting returns from the trends. But with the latest looks moving in and out of favor faster than NASDAQ's tech stocks, many leading ladies came out losers—looking silly (Portia de Rossi) and confused (Jennifer Love Hewitt). Our best tip: Buy smart, sell tomorrow.

JUDGES
WHAT DO YOU GET when you ask five strangers to look at more than 200 photos of some 30 celebrities and then offer an opinion? Surprisingly, a consensus: Getting dressed is fun, but it's not always easy. Not for the stars—and not for our judges themselves. Indeed, while we were busy crunching numbers—the top 10 candidates made our best-dressed list, the bottom 10 our worst-dressed list, and those left in the middle eliminated—our panelists reflected on their own styles. And they realized that now and then, bad clothes happen to even really good dressers. Take it from Iraeli-born designer Elie Tahari, 48, whose line of women's career wear has earned him the nickname King of the Jacket. "I don't think I was born with a sense of style," he says. "It takes practice." Plus-size model and actress Mia Tyler, 21—half sister to actress Liv Tyler—has spent a lifetime looking at the rock-star wardrobe of her father, Aerosmith lead singer Steven Tyler. Does that make her oops-proof? Hardly, she admits. "My dad and I share a problem with matching." Quadruple-platinum-selling singer Sisqó, 24, likes to stick out in a crowd. His personal statement, he says, "is 'Look at me.'" Sure, he slips up sometimes, he confesses, "but you won't see me make a fashion mistake twice." Designer Dana Buchman, 48, likes "luxurious and timeless clothes," but isn't above dabbling in trends—such as her cherished jaguar-print stretch velveteen jeans. But Ben Stein—the 55-year-old presidential speechwriter turned Emmy-award-winning host of Win Ben Stein's Money on Comedy Central—wouldn't be caught dead in velvet. Anymore. "I did wear a blue-velvet suit once," he says. "I was trying to be hip, but it was a very big mistake." And so he discovered the source of real style. "I dress like what I am," says the conservatively clad Stein, "and I never want to change."

Heather
Locklear
IF ROCK STARS never die, why should their wives abandon their skintight sequined scene-stealers? From Dynasty to Melrose Place to Spin City, from first husband Motley Crue drummer Tommy Lee to her current mate of five years, Bon Jovi guitarist Richie Sambora, 41, prime-time siren Heather Locklear has spent nearly two decades living—and dressing—on the edge. And as our panelists see it, neither motherhood (daughter Ava Elizabeth is 3) nor the ever-closer call of middle age (she turns 39 this month) is mellowing her mettle. "She has great presence," says model Mia Tyler. "When you're backstage all the time, there's a rock and roll edge you pick up. You can tell she's got it." No argument from singer Sisqó. "Everything clicks with her," he raves. Although jeans, T-shirts and sneakers are the toddler-proof uniform the 5'5" Locklear wears at home in L.A., her heart, she recently told USA Today, is where it has always been: squeezed into "pretty sexy tight things."

The other BEST DRESSED:
Jennifer Aniston, Freddie Prinze Jr., Britney Spears, George Clooney, Prince William, Samuel L. Jackson, Pierce Brosnan, Charlize Theron, Kevin Spacey

The WORST DRESSED:
Portia de Rossi, Jennifer Love Hewitt, Lucy Liu, Renée Zellweger, Bruce Willis, Lara Flynn Boyle, Lil' Kim, Lauren Holly, Bebe Neuwirth, Christina Aguilera