"Silver Linings Playbook" star Bradley Cooper went for the classic tux look.
A familiar face at such awards, Naomi Watts dazzled in her pearly white Marchesa dress.
"Zero Dark Thirty" star Jessica Chastain donned a scarlet Alexander McQueen dress to match her crimson locks.
Daniel Day-Lewis, nominated for his starring role in "Lincoln," wore a classic bowtie.
Helen Hunt donned a silver necklace with her gown.
Julianne Moore, nominated for "Game Change," chose a white, floral-patterned Chanel Haute Couture dress for the evening.
Nicole Kidman donned a sleek, dark Vivienne Westwood dress for the show.
Nominee Anne Hathaway chose a black Giambattista Valli Haute Couture mini with a sheer skirt for her walk down the red carpet.
On the red carpet, Harvey Weinstein makes a last-minute check for important emails before heading inside.
"Modern Family's" Ty Burrell attended the award show with his wife, Holly.
Ariel Winter, the young "Modern Family" star, wore a pale-colored gown reminiscent of a Disney princess.
Fellow "Modern Family" star Aubrey Anderson-Emmons took to the red carpet in a white dress and tights.
The "Modern Family" cast was united at the event, with Eric Stonestreet -- a.k.a. Cameron Tucker on the show -- making an appearance in a slick black tuxedo.
Edie Falco, the star of "Nurse Jackie," chose an understated blue dress for her red carpet walk.
Peter Facinelli and Vitalie Taittinger opened the 19th annual Screen Actors Guild award ceremony with a champagne Taittinger toast.
"Fashion Police" host Kelly Osbourne sported a sleek new cobalt-colored updo.
"Glee" star Jayma Mays wore a sophisticated, sleeveless dove-white dress.
Carmen Electra went for a dark dress for this year's show.