Carolyn Tastad

In January the Canadian-born Tastad became the new head of P&G’s struggling North America division. She now oversees P&G’s largest market, with approximately $30 billion of the company’s $76.3 billion in sales, though the unit has shrunk as P&G sells off nonperforming brands. It’s a tough go at P&G right now: In the fourth quarter of fiscal 2015, P&G’s overall sales fell 9%.

For more on newcomers and returns to the list, read “Who's on? Who's off? Fortune's list of the Most Powerful Women has plenty of changes.”