Horowitz, who currently serves as VP of original programming and production at ABC sister network ESPN, will oversee all three aspects of "Today" -- the morning shows, the website and the concert series at Rockefeller Plaza -- effective Dec. 1.
NBC has been working to bring Horowitz on board as early as January; he will be ending his ABC contract early.
Horowitz will report to NBC News president Deborah Turness and will oversee Don Nash, Dee Dee Thomas and Jen Brown.
"With so much momentum at the 'Today' show in recent months, we want to drive even greater integration and growth among all parts of the brand, on all platforms," Turness said in a staff memo. "This requires someone who can lead the various hours of the weekday show, 'Weekend Today,' Today.com, and the Plaza experience."
The show has made several staff changes in the year since Turness took office. Rob George was hired as director, and longtime producer Melissa Lonner, who booked concerts, left the show.
"This is an exciting and invigorating opportunity, and I am humbled to work with one of the most indelible brands in television," Horowitz said in a statement.
Since Horowitz was charged with developing new programs at ESPN, he will explore new formats beyond the existing broadcast and digital platforms, such as extensions in digital, e-commerce and events, at "Today."
At ESPN Horowitz oversaw a number of shows, including "Olbermann," which brought Keith Olbermann back to ESPN; the sports debate show "First Take"; "SportsNation"; and the Sports Emmy-nominated "World Series of Poker."
He worked at NBC Sports before joining ESPN in 2006. Horowitz began his TV career as an NBC Olympics researcher in 2000 and won four Sports Emmys for his work on coverage of the Olympics and the NBA on NBC.
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