Rihanna always looks great on the red carpet, and she looked fabulous at her 1st annual Diamond Ball event, which took place at The Vineyard in Beverly Hills, Calif., on Thursday night (Dec. 11).

After announcing the event in November, RiRi welcomed stars like Kim Kardashian, Jimmy Kimmel and Salma Hayek to the charity shindig.

Rihanna looked stunning in a crimson Zac Posen off-the-shoulder full-length gown with a sweetheart neckline. Later, the 'Stay' singer changed into a midnight blue Zac Posen ball gown and performed a medley of her hits, including 'Diamonds,' 'Pour It Up,' 'Umbrella' and 'Run This Town,' with a live orchestra.

Detroit rhymer Big Sean closed out the event with a performance of 'Clique' and even performed his kiss-off anthem, 'IDFWU,' as guests sang along.

The Diamond Ball benefits The Clara Lionel Foundation, which she founded in 2012 on behalf of her grandparents, to improve the quality of life in health, education, arts and culture in communities around the world. And perhaps the sweetest moment was seeing Rihanna walk in arm-in-arm with her grandfather, Lionel Braithwaite.

Check out the gallery above as well as her Instagram posts and performances below to see how the event unfolded.

Watch Rihanna perform 'Diamonds' with an orchestra

Watch Rihanna perform 'Pour It Up' with an orchestra


Une photo publiée par badgalriri (@badgalriri) le

@mdollas11 #IDFWU THANK YOU to our surprise special guest @bigsean came thru and to' it up real quick

Видео опубликовано badgalriri (@badgalriri)