Ruth Porat is Google's new CFO. Craig Barritt/Getty Former Morgan Stanley CFO Ruth Porat is moving to Google as its new CFO, replacing Patrick Pichette, who announced his retirement on March 10.

Porat, who has been called "the most powerful woman on Wall Street," first joined Morgan Stanley in 1987, filling numerous roles before becoming CFO in January 2010.

There she advised many of the firm's biggest tech IPOs, including Amazon and eBay, and played an important role during the financial crisis, advising the US Department of the Treasury on Fannie Mae and Freddie Mac and the New York Federal Reserve Bank on AIG.

She almost left Morgan Stanley in 2013 to run for deputy Treasury secretary of the US, but she withdrew her name "in part because she did not want to face questions about her finances and was worried about a highly charged environment in Washington against Wall Street bankers," The New York Times reported at the time.

Porat will take the reins as Google's new CFO on May 26 and will report directly to CEO Larry Page. She joins Google at a time when investors and analysts are panicking about how the company's search advertising revenue growth is slowing. Pichette, who was Google's CFO since 2008, was referred to as the company's "secret weapon," known for bringing rational thinking to Google's cost structure, helping the company introduce new revenue-generating products, and cutting some that could not make money. During the company's latest earnings call, however, he was grilled about Google's significant 2014 investments given its revenue and EPS misses.

"I'm delighted to be returning to my California roots and joining Google," Porat said in the company's announcement on the news. "Growing up in Silicon Valley, during my time at Morgan Stanley and as a member of Stanford's Board, I've had the opportunity to experience firsthand how tech companies can help people in their daily lives. I can't wait to roll up my sleeves and get started."

Porat earned her bachelor's in economics and international relations from Stanford University, and she has master's degrees from the University of Pennsylvania's Wharton School and the London School of Economics (where she studied industrial relations). She is also a breast cancer survivor who has been vocal about the importance of finding the right "mix" of family and work, though not necessarily a work-life "balance."

Morgan Stanley has named investment banker Jonathan Pruzan as its new CFO.

Here's Google's blog post with the announcement: