Michael Tilson Thomas, the charismatic conductor and composer who won 12 Grammys and presided over the San Francisco Symphony for 25 years, the London Symphony Orchestra and the Los Angeles Philharmonic, has died. He was 81.

Tilson Thomas died Wednesday in his home in San Francisco of glioblastoma, it was announced on his website. He underwent brain surgery to remove a tumor in 2021 after being diagnosed with glioblastoma multiforme and announced the tumor had returned in February 2025.

Two months later, he conducted his final concert with the San Francisco Symphony.

A pianist and protege of West Side Story composer Leonard Bernstein, Tilson Thomas was known for his energetic interpretations of Austria’s Gustav Mahler. He specialized in music from Russia and work by Americans George Gershwin and Aaron Copland as well.

The 2010 National Medal of Arts recipient and 2019 Kennedy Center honoree also had a reputation as a bad boy of classical music, once leaving the stage at the Hollywood Bowl to protest noise from a police helicopter.

Tilson Thomas served as the San Francisco Symphony’s 11th music director from 1995 until he resigned following the 2019-20 season. His work as a composer included From the Diary of Anne Frank, a UNICEF commission that premiered in 1991 and was narrated by Audrey Hepburn.

Tilson Thomas was born in Los Angeles on Dec. 21, 1944. His father, Theodor Thomashefsky, was a producer who worked for Orson Welles’ Mercury Theater Company and later for Roy Rogers cowboy serials, and his mother, Roberta, was a researcher at Columbia Pictures. Grandparents Boris and Bessie Thomashefsky were founding members of the Yiddish Theater in America.

Tilson Thomas started playing the piano at age 3, had a musical epiphany by 13 when he listened to Mahler — “I was so shocked to discover that it described the shape of my own unresolved life,” he told The Guardian in 2012 — and at 19 was named music director of L.A.’s Young Musicians Foundation Debut Orchestra.

Later, he conducted the full L.A. Phil for youth concerts and studied at USC under Jascha Heifetz and Gregor Piatigorsky. He first met Bernstein in 1968, and the two began working together in New York.

In his mid-20s, he became assistant conductor of the Boston Symphony Orchestra and was a sensation after making his New York debut at Lincoln Center.

Tilson Thomas was a guest conductor of the L.A. Phil in the 1980s and the principal conductor of the London Symphony Orchestra from 1988-95, taking it on tours in Europe and the U.S. In 1987, he co-founded the Miami-based New World Symphony to prepare young musicians around the world for careers in classical music.

In 2009, he created the YouTube Symphony Orchestra, made up of young players from 30 different countries, to give a concert that could be watched on the internet.

Joshua Robison, his husband and manager, died in February at age 79.

“I think I’m somewhere between a director and a sports coach,” Tilson Thomas told The Guardian. “You recognize how uniquely talented the different musicians are and try to imagine how they can come to the fore in performance. No good director, working with a particular cast, would try and force them to be something other than what they are. Nor would a good director say to an actor, ‘Say the first three words quickly, then the next two slowly,’ and so on for the whole of the play.

“The point is that the actor must become the role. It’s the same with music. You try to show the musicians ways they can make the most out of the music and get the most out of each other.”