The event: The UCLA Hammer Museum's12th annual Gala in the Garden on Oct.11 honored Joni Mitchell, the singer-songwriter and painter whose sonic style has been described as "painting with words," and artist Mark Bradford, who is known for his large-scale, multilayered, collaged works incorporating urban ephemera, including maps and street posters.

The scene: The sold-out event, which raised $2.5 million for the Hammer's exhibitions and public programs, was held in the museum's outdoor courtyard. Before dinner, cocktails were served upstairs, and the museum's current exhibitions, featuring work by Jim Hodges, Robert Heinecken and others, were open for viewing.

Art world stars, including John Baldessari (showing his fashion team colors by wearing a Rodarte sports jersey), Ed Ruscha, Doug Aitken, Catherine Opie, Lari Pittman, Barbara Kruger and For Your Art's Bettina Korek, mingled with the philanthropic crowd and the Hollywood set, including Demi Moore, Julia Roberts, Tracee Ellis Ross, Kate Bosworth and husband Michael Polish, Rashida Jones, January Jones, Zoë Saldana, Orlando Bloom, Sam and Aaron Taylor Johnson, Tony and Liz Goldwyn and Emily Blunt and husband John Krasinski.

The program: Hammer Museum Board Chair Marcy Carsey, Hammer Museum Director Ann Philbin and Los Angeles Mayor Eric Garcetti kicked off the festivities, praising the work of the museum and suggesting that through the vibrant L.A. art scene, the city is entering a new golden age.

Filmmaker Cameron Crowe introduced Mitchell, sharing that when he was a rock music journalist, the notoriously press-shy Mitchell was the interview he wanted most. When they did meet, she inspired him immediately. "Utter honesty is the active ingredient of everything she does," Crowe said. In describing her aesthetic sense, he noted that she was "the first rock artist to breach the antifashion model of dressing," noting the sparkling boho dresses she wore during her "Court and Spark" period in the early 1970s.

When Mitchell took the stage, she explained that the look was actually a response to her mother saying she dressed too much like a hippie and should be more elegant. She repeated a quote she's often said, "I think of myself as a painter first and a musician second," then thanked Crowe and the museum for their support. She also used the opportunity to plug another event she has coming up at the Hammer on Nov. 6, which will feature a screening of "The Fiddle and the Drum," a ballet set to her songs.

Art historian Sarah Lewis introduced Bradford, highlighting his innate curiosity, beginning when he was a child and used to go to the airport to observe people getting off planes from faraway lands. "He has walked the world to find the sublime," she added.

Bradford praised the Hammer for taking him in right out of art school, and said that although he grew up between the worlds of Santa Monica and his mother's hair salon in South Los Angeles, it didn't matter. "You don't have to hide certain parts of your life," he said.

After dinner, pop star Sia performed three songs to wind down the party.

Fashion notes: Several guests wore looks by Bottega Veneta, the evening's sponsor, including January Jones in a rose silk jacquard dress and Ross in a wool dress with leather insets. But Bottega Veneta creative designer Tomas Maier was a last minute no-show. I did spot designers Ashley Olsen, Kate Mulleavy, Scott Sternberg and Corey Lynn Calter.

And Bosworth stole the best dressed award in a dramatic backless white satin gown by Alexandre Vauthier.