Ann Sarnoff marked her first day as Warner Bros. CEO with a memo to employees calling for innovation but taking note of significant changes at WarnerMedia and elsewhere.

The former Viacom and BBC executive surprised most Hollywood handicappers in winning the job, but her many backers extol her calm and determined style.

In a memo to employees Thursday, Sarnoff didn’t avoid Topic A at the company, which is the dramatic scope and speed of change that has been reshaped it since AT&T bought Time Warner and renamed it WarnerMedia. The CEO job also opened up due to sensitive circumstances when Kevin Tsujihara stepped down after his interactions with actress Charlotte Kirk gained press attention. While he denied through his attorney having had a direct role in any casting matters pertaining to Kirk, Tsujihara wrote a memo to employees expressing “regret” over causing embarrassment to the company and its workers.

Sarnoff didn’t look toward the past administration but offered a tacit acknowledgement of the turnover.

“Despite the many changes that have occurred across the industry and here at the company, your focus and commitment to excellence have kept us on track to realize our ambitious goals,” Sarnoff wrote. She gave shoutouts to Toby Emmerich, Peter Roth and Kim Williams for serving as an interim CEO trio in the period between Tsujihara’s exit and her arrival.

Warner Bros. has kept its film operations running fairly smoothly in 2019 (despite some recent disappointments) but it is now contending with a Fox-fortified Disney at the box office. In television, it faces a complete reshaping of the landscape as media companies (including WarnerMedia) mount massive streaming efforts in a bid to close the gap with Netflix. The No. 1 strategic question facing top suppliers like Warner Bros. Television is whether they will be able to continue to play the field and maximize profits from shows or whether they will increasingly tailor their efforts to suit the emerging streaming operations.

“This is an exciting—and challenging—time in the entertainment industry, and we need to keep looking at new business models, new competitors, new content platforms and formats—and finding new opportunities,” Sarnoff wrote. “With our talent, expertise and unmatched IP, we’re in a great position to capitalize on them.”

Sarnoff urged employees to attend a September 4 town hall, promising more details would be relayed soon.

Here is the full memo: