Nina Tassler will be replaced at the helm by her chief lieutenant Glenn Geller

Credit: Cliff Lipson/CBS; Sonja Flemming/CBS

Longtime CBS executive Nina Tassler has decided to step down from her role as chairman of CBS Entertainment at year’s end.

Tassler, who first joined the network in 1997 as a development executive, helped to make CBS the most-watched network for 12 of the past 13 years with crowd and critical faves like The Big Bang Theory, The Good Wife, How I Met Your Mother and Scorpion, among others. She also launched The Talk, as well as The Late Late Show with James Corden and, just last week, The Late Show with Stephen Colbert.

Tassler was named entertainment president in 2004 before recently earning the title of chairman.

“CBS is a special place,” said Tassler in a statement. “For the past 18 years, I’ve been blessed to be part of an amazing team that has lifted this network to an enviable run of success. It all starts at the top with [CBS Corp. CEO] Leslie Moonves, my boss, mentor and friend for two and a half decades, and a leader who inspires excellence in every part of the creative and business process. I owe a tremendous debt of gratitude to Leslie, my colleagues at CBS and all the actors, producers and writers who were part of this incredible journey. I will always love this place, yet it is time for my next chapter, and I’m thrilled that I can pursue my other creative interests while still being part of the company.”

Tassler’s chief lieutenant, Glenn Geller, will immediately assume the role of president of CBS Entertainment, overseeing all primetime, daytime and late night programming. He’s been with the network since 2001.

After she officially steps down as chairman at the end of the year, Tassler will stay on board as a consultant through at least 2017.

“Nina and I have been colleagues and friends for 25 years,” said Moonves in a statement. “It is one of the proudest partnerships of my professional life. We’ve enjoyed amazing success together, both here and at Warner Bros., and it’s been a privilege to watch her talents and accomplishments grow. Nina is a creative executive with the instincts of an artist, so it came as no surprise that she would eventually want to express those talents beyond television. All of us here are grateful and proud of CBS’ success with Nina leading our entertainment programming, and we will be the biggest fans for all her future endeavors.”

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