Josh Tyrangiel has stepped down as head of Bloomberg Businessweek and will be replaced by deputy editor Ellen Pollock.

Pollock’s ascension marks the first time a woman has led the publication. She joined Businessweek eight years ago after a stint at the Wall Street Journal.

On Twitter, Tyrangiel thanked the company’s chief Michael Bloomberg for tapping him and remembered his stint at the magazine as “golden years for me.” In an interview with the New York Times, Tyrangiel said that he had a new opportunity lined up, but did not offer additional details, and described the split after six years with the company as amicable.

His exit comes as Bloomberg’s media operations are narrowing and deepening their focus. The company laid off roughly 100 journalists last month as it tries to concentrate more intensely on six key areas: business, technology, economics, finance, markets and government.

It also follows the appointment earlier this year of The Economist’s John Micklethwait to oversee Bloomberg’s editorial operations.

In a memo to staff, Micklethwait wrote, “Right from the beginning, Josh told me that he was a restless soul and that at some time in the next year or so he would move on. I am sad that it will be tomorrow, but we should all be extremely grateful for all that he has done for Bloomberg, across all our platforms.”

Prior to joining Businessweek, Pollock was at the Journal for 18 years, serving as deputy page one editor and as a senior writer covering corporate fraud and legal issues. She also had stints at the American Lawyer magazine and the Manhattan Lawyer, and authored two books, “The Pretender: How Martin Frankel Fooled the Financial World and Led the Feds on One of the Most Publicized Manhunts In History ” and  “Turks & Brahmins.”
Her predecessor at Businessweek had kind words for his replacement.
“No one waves the flag for great journalism higher (or louder) than Ellen,” Tyrangiel wrote in a message to staff. “She’s an inspiration—and the best editor I’ve ever worked with. The magazine would be no good, and no fun, without her.”