Warner Bros. is shaking up its film studio.

As part of a major reorganization, Toby Emmerich is being promoted to chairman of Warner Bros. Pictures Group, while Sue Kroll, the president of worldwide marketing and distribution, is relinquishing her role for a three-year producer deal on the Burbank lot. Kroll has been with the studio for decades and has deep relationships with filmmakers and stars such as Christopher Nolan, Clint Eastwood, and Tom Cruise. She will become a producer on the lot.

As part of the shake-up, Blair Rich will head global theatrical and home entertainment marketing. Rich has been courted by several studios in recent months, and is highly valued internally. She was one of the masterminds behind the marketing campaign for last fall’s blockbuster “It.” In addition, Ron Sanders will serve as president, worldwide distribution at the studio, assuming responsibility for global theatrical distribution while retaining his role as president of the home entertainment group.

Under the new management structure, production, marketing, and distribution will report to Emmerich.

In 2016, Emmerich was promoted to president and chief content officer at the studio after a long run overseeing New Line, the Warners division responsible for “The Conjuring” and “Lord of the Rings” franchises. His latest promotion gives him more authority and autonomy. Warner Bros. chairman and CEO Kevin Tsujihara will take a step back from day-to-day oversight of the movie operations.

“I’m humbled and honored to have this opportunity to help continue Warner Bros. Pictures’ legacy of creativity, innovation and excellence,” said Emmerich in a statement. “We will remain focused on being the first choice for the world’s best filmmakers, whether they’re making their first film or their 34th.”

Tsujihara, who has long been contemplating changes in the movie division, made the decision to restructure its management over the Christmas holidays. In an interview with Variety, he said that he didn’t want to promote Emmerich until he’d had time to wrap his hands around the studio’s production apparatus.

“Now is the right time to do it,” said Tsujihara. “He’s had year under his belt working with the production team, and that’s been valuable experience, and he’s ready.”

Warner Bros. had a strong 2017, scoring with the likes of “Wonder Woman,” “Dunkirk,” and “It.” However, Emmerich and his team face challenges. With the exception of “Wonder Woman,” its DC Comics films have earned a critical drubbing, and the most recent release,”Justice League,” was a box office disappointment. There is also the challenge of matching Disney’s fire power — the studio owns Marvel, Pixar, and LucasFilm. If a deal with Fox gets governmental approval, Disney stands to get even bigger, buying a film library that includes “X-Men” and “Avatar.”

The studio overhaul takes place at a tense time for Time Warner, its corporate parent. The Justice Department has sued to block its $85.4 billion sale to AT&T, claiming it has the potential to create a monopoly. AT&T is currently challenging the government in court, but the outcome remains uncertain.

Tsujihara said that bringing together the film and home entertainment marketing and distribution operations will help the company more “strategically” manage its releases. He also stressed that Warner Bros. is in a strong position, noting that the studio’s global box office haul in 2017 topped $5 billion.

“We’re actually making this change at a time of strength,” he said. “We just had the biggest box office in the history of Warner Bros. It’s not a situation where something was broken.”

Industry-wide the forecast is gloomier, particularly in North America. Domestic ticket sales were down 2.3% and attendance in North America fell to a 27-year low. Overseas, the picture was brighter with worldwide receipts hitting a record $28.8 billion.

“The trends from an attendance perspective have been more challenging domestically than internationally,” said Tsujihara. “You have more options for consumers than there were five years ago, ten years ago, fifteen years ago. Usage on YouTube and social media is up. People are spending a significant time on video games. The bar has been raised significantly on what consumers are willing to pay for. You have to increase the quality of the movies and make the experience better and put out movies that resonate.”

The Rich and Sanders promotions are effective immediately. During the transition, Kroll will report to Tsujihara as a special advisor on the restructuring, including overseeing the high-awards campaigns for “Dunkirk” and “Wonder Woman,” as well as advising on upcoming releases such as this spring’s “Ready Player One.” She will transition to an exclusive producer deal on April 1.

“Sue is going to be an incredible producer,” said Tsujihara. “She’s going to continue to be a major force.”

Kroll’s future at the studio has been grist for the rumor mill for years. She was seen on the lot as a divisive and demanding figure, but a person who was highly skilled at selling movies, while being very adroit at navigating studio politics. There had been speculation she might be eyed for a role at Paramount, Netflix, or another studio looking for marketing prowess. From her new office on the Burbank lot, Kroll will produce “A Star is Born,” a remake of the oft-filmed romantic drama with Bradley Cooper and Lady Gaga, and “Motherless Brooklyn,” an adaptation of the best-selling Jonathan Lethem detective story with Edward Norton. Other titles will be announced shortly, the studio said. Her production company will be housed on the lot in a bungalow formerly occupied by Jack Warner, and the pact is exclusive.

“I’ve had a wonderful career here at Warner Bros.,” said Kroll in a statement. “For the past two decades, I’ve had the privilege of working with some of the most interesting and illustrious filmmakers of our age, and I’ve helped bring their incredible work to many millions of people around the world. Along the way, I have built and worked with a fantastic team of people here at the studio. Together, we’ve broken boundaries and redefined what’s possible, and I’m proud of all that we’ve achieved. Blair Rich, who’s a terrific executive, will lead the marketing team into the next phase of our industry’s evolution, and I know she’ll be great.”

[Updated with quotes from Tsujihara at 8:00 p.m. EST]