Britney Spears is bringing sexy back!

The singer was one of the celebrity guests at Wednesday night's City of Hope Awards in Los Angeles -- where she showed up wearing a backless white gown that showed some major skin.

The 30-year-old mother of two looked flawless at the event, sporting some amazing hair extensions and some fresh makeup.

Also helping her overall look: Fiance Jason Trawick, who posed alongside her in a suit.

Britney wasn't the only blonde bombshell at the party though.

Miley Cyrus performed at the event, stepping out in a studded, zip-up top and full-length white skirt. She also showed off her short new 'do and her sparkly engagement ring from fiance Liam Hemsworth.

Other star sightings included a svelte Jordin Sparks, "American Idol" runner-up Jessica Sanchez and "X Factor" wannabe Sophie Simmons.

Check out all the arrival shots in the gallery above!