When the world’s most powerful people jet off to the annual summit hosted by Allen & Co. in Sun Valley, Idaho, to brainstorm and talk deals, they adopt a sartorial style we might call mogul casual.

The latest confab, which has become popularly known as the Billionaire Summer Camp as it has garnered increasing media attention in recent years, happened this week, attracting the likes of OpenAI’s Sam Altman, Meta Platforms Mark Zuckerberg, Apple’s Tim Cook and many others from Silicon Valley. High-profile names from Hollywood (Disney’s Bob Iger and Warner Bros. Discovery’s David Zaslav, among others) and media (CBS’ Gayle King, CNN’s Van Jones) also attended. So did Wendi Murdoch and Jonathan Haidt, author of “The Anxious Generation.”

No one showed up in suits and loafers—they mostly packed quarter-zip sweaters and sneakers. All-American denim was also out in force, along with jet-black tees and sturdy overshirts equipped to combat the evening temperature dip. Not everyone looked so plain Jane: For instance, Karlie Kloss and British activist and actress Nazanin Boniadi shook up things in more colorful, graphic attire. And truly, hats off to Naveen Rao, the former Databricks executive and founder of Unconventional AI, and the other folks who eschewed boring ol’ baseball caps and went for Stetson-style headgear instead.