One of the year’s most buzzed-about art auctions is set to kick off this weekend, but it isn’t hosted by Sotheby’s, Christies, or any other house. It’s the annual benefit auction for the Leonardo DiCaprio Foundation, which is celebrating its 20th anniversary this year.

The event, on September 15, has been scaled back from its four lavish previous iterations in St. Tropez, yet it’s nonetheless expected to be a star-studded affair. Hosted on a sustainable vineyard in California’s Sonoma County, the zero-waste evening will feature an art auction, celeb attendees like Edward Norton, Tobey Maguire, and a special performance by Coldplay singer Chris Martin. Oh, there will also be a live hawk flying around.

The event expects to host around 300 guests (down from 1,000) and an auction with 20 lots (down from about 50). But the reduction in quantity doesn’t mean a sacrifice in quality. The auction will offer a mix of big-name and emerging artists, including paintings by Jack Goldstein, Matthew Wong, and Jonas Burgert; sculptures by Ai Weiwei, Fred Wilson, and the Haas Brothers; a Richard Prince C-print, a David Hockney iPad drawing on paper, and a mixed-media work by Cory Arcangel.

The Leonardo DiCaprio Foundation’s inaugural gala at Domaine Bertaud Belieu in 2014 in Saint-Tropez. Photo: Pierre Suu/Getty Images.

DiCaprio enlisted art advisor Lisa Schiff, who’s worked with the actor and his foundation for four years, to organize the auction, which raises funds for wildlife and environmental causes. “I didn’t want the usual suspects,” Schiff tells artnet News. Instead of bringing in overexposed artists who appear often at benefit auctions, she solicited those who are buzzworthy but not over-hyped; rigorous but also capable of bringing in money for the foundation. “The long game is better than the short game. If the work is good, then in the long run, the buyers will have artwork of lasting value.”

Ai Weiwei, Forever (Stainless Steel Bicycles in Silvery), 3 Pairs 8 Layers (2013). Courtesy of the artist and the Leonardo DiCaprio Foundation.

Benefit auctions can be tricky affairs for artists, who are frequently asked to donate works to charitable causes and don’t always get to oversee the results. “This year I asked myself, ‘How can I make the auction work for the artists?’” Schiff says. “I looked for artists who aren’t getting the kind of mass attention that other artists are, who would actually benefit from the auction. I wanted to avoid including any speculatively-hyped artists in the auction, because they’re the ones who actually get hurt and they bring in the wrong people.”

David Hockney, The Arrival of Spring in Woldgate, East Yorkshire in 2011 (2011). Courtesy of the artist and the Leonardo DiCaprio Foundation.

One of the highlights in the sale is a six-foot-tall Wayne Thiebaud painting, Mountain Split (2011-17), which is valued at roughly $4.5 million. Thiebaud, who turns 98 this year, will also be honored with the foundation’s inaugural Art and Environment Award, recognizing an “individual’s significant and sustained contributions to innovative artistic practice that foregrounds art, and its ability to encourage engagement and action, as a cornerstone of public life.”

Wayne Thiebaud, Mountain Split (2011-17). Courtesy of the artist and the Leonardo DiCaprio Foundation.

Arne Glimcher, the founder of Pace Gallery, will also be celebrated with the foundation’s Lifetime Achievement Award conservation. (Little known fact: Glimcher was a producer of the 1988 film Gorillas in the Mist.) Mini exhibitions devoted to both Thiebaud and Glimcher will be on view at the event, in custom booths designed by architect Annabelle Selldorf.

This is the fifth auction the foundation has held since its founding in 1998. Reports have estimated previous fundraising totals at between $30 million (in 2017) and $45 million (2016), though expectations are a bit lower this year given the number of lots. The auction is open for online bidding now.