James Conlon will step down as music director of the Ravinia Festival after the 2015 season.
A guest conductor at Ravinia since 1977, Conlon took over as music director in 2005. He said he is leaving to devote himself to other projects, both musical and personal.
An internationally renowned opera conductor, Conlon, 64, also serves as music director for the Los Angeles Opera.
During his tenure, Conlon provided Ravinia attendees with many "magical moments," said Ravinia President and CEO Welz Kaufman, referring to Conlon's multi-year Mahler cycle, his showcase of Mozart's piano concertos and operas, and his leadership in reviving works by composers whose music the Nazi regime suppressed. For those efforts, Conlon received the first Zemlinsky Prize, named for Austrian composer Alexander Zemlinsky.
"James has made an enormous contribution internationally in rescuing these composers and their music from obscurity. His championing of this music has become a worldwide calling card and a cause that achieved particular impact at Ravinia," Kaufman said in a prepared statement.
John Anderson, chairman of Ravinia's board of trustees called Conlon "a true believer" and praised his musicianship, artistry and "boundless capacity for empathy."
"He will be missed almost as much as he is admired," Anderson said.
Conlon's final conducting appearances next summer will reprise favorite programs from earlier in his 11-year tenure.