Red dress by Angel Sanchez

Rachel Taylor, 36; "life purpose" coach with her own business, Break Free
"I need froufrou," says Rachel. "A theatrical Moulin Rouge look is a big part of my style." Which is why the poufy skirt of this mischievous dress (Angel Sanchez) didn't faze her (besides, it's terrific hip camouflage). Matching satin shoes (Jimmy Choo) and Burma rubies (Avicci earrings and bracelet) reinforce red's intrinsically ebullient mood.
Three colorful dress options

Laurie Ogle, 49; mother
Not your grandma's lace. A lined maroon sheath with a chic beaded belt and the surprise of casual pockets (Monique Lhuillier) is perfect for Laurie's (left) pared-down style: "Anything with too many doodads isn't for me." Even the shoes—open-toe brocade (Nina)—are a subtle update of tradition. Jennifer Miller earrings.

Kyessa L. Moore, 25; graduate student in African-American studies
For holiday photo ops, seek out a brilliant satin dress (Donna Ricco, $158) with curve-friendly ruching ("I'm a runner," Kyessa (center) says, "but I have a stomach"). It's not cheating to wear a slimming bodysuit underneath. Mark Walsh Leslie Chin cuff and earrings. Nina shoes.

Heide Alaia Byun, 39; fashion retail salesperson
"Dresses are no-brainers: Put one on and you're good to go," says Heide (right), whose party prep time is a mere 30 minutes ("I'm always waiting for my fiancé"). This sunburst of a number with a train (Prada) has such drama that accessories—yellow sapphire and diamond bracelet (Avicci); brown sandals (Delman)—are all she needs.
Two dresses with color, not clutter

Jane McCormick, 62; retired
Here's a dress that's all about color and uncluttered structure (CH Carolina Herrera, $1,500)—which suits Jane, who hates "anything poufy, flowery, frilly" and likes purple with her silvery hair. The belt is patent (CH Carolina Herrera), add heels to match (Fendi). Diamonds (Asprey earrings; Avicci bracelet) supply sparkle.

Sandra Jamron, 33; pharmacy chain co-owner
Bronze and plum stripes (the rep-tie kind) bring an unexpected menswear feeling to this bubbly dress (Rickie Freeman for Teri Jon, $640), and a wrap-style bodice makes the waist look smaller. Sandra is crazy for the jeweled ankle straps (Juicy Couture): "My eyes light up when someone says, 'Shoes!'" H. Stern earrings. Kara Ross cuff.
From workday to wow in one dress

The Office
Kat Schaffer, 45; real estate broker, candidate for a master's in social work

A crisp trim and witty pockets give this dress (left, Vera Wang Lavender Label, $395) nine-to-five credibility; a dose of black seals the deal (White + Warren cardigan; DKNY tights; Manolo Blahnik flats). Businesslike extras include drop earrings (Ted Muehling) and a good-sized bag (Laundry by Shelli Segal).

The Office Party
When you enter the social whirl straight from work, you may clock 14 hours in the same dress: "I like soft fabrics," Kat says. "I have to be comfortable." Here (right) she's ditched the tights, traded the sweater for a silk and velvet wrap (Blanc de Chine), and acquired a spectacular beaded purse (Beavaldes). H. Stern earrings. Cole Haan T-straps.
Create a casual, festive or formal look.

Dress Code: "Casual"
Harriette Mandeville, 61; actress and leader of meditation workshops

"Wearing one piece means I don't have to figure out what goes with what," Harriette (left) says. This low-priced stretch charmeuse number (Isaac Mizrahi for Target) makes life simple. For informal evenings, ground it with black: a swingy jacket (H&M), wristlet (Dior by John Galliano), and shoes (Rodo). Anthony Nak earrings.

Dress Code: "Festive"
Hitha Prabhakar, 31; fashion editor and stylist

"People let go at end-of-the-year parties," Hitha (center) says. "They're more unguarded." To match that happy mood, we punched up the fuchsia strapless (a built-in bra means you don't need special lingerie) with high-intensity accessories: an embellished necklace worn as a belt (Beavaldes), glam earrings (Kenneth Jay Lane), and metallic shoes (Rodo) that can dance all night.

Dress Code: "Black-Tie Optional"
Marina Aris, 33; financial adviser

"Dresses make me feel va-voom!" Marina (right) says. This time, our sheath goes formal with diamond jewelry (Tiffany & Co. studs; Fauxsie by Baby Doll Gems choker; Asprey bracelet) and a filmy wrap that's just a length of tulle (B & J Fabrics). Stuart Weitzman shoes.