Some experiences are hard to appreciate until they're over.

But Ellen Alemany is grateful for one particularly tough boss who grilled her with such intensity that she would review for every meeting as if studying for a test.

"He always told me, 'You really have to know your stuff if you want to continue progressing in your career,'" says Alemany, who has progressed so well she now runs the $140 billion-asset Citizens Financial Group Inc. Alemany long wanted to be in charge of a bank and managed her career with that goal in mind. She worked two decades at Citigroup, taking assignments over the years to lead different business lines at home and abroad, to get the experience it would take for her dream job.

Two years in, she enjoys it as much as she imagined, even though she started at Citizens just before the financial crisis hit. She describes the experience of navigating her company through such a monumental challenge as "surreal but exhilarating."

Conducting town halls every six months to update employees helped provide essential reassurance, she says. Employees told her that they knew everything was fine, "because if it was really a crisis, I would've been locked in my office."

She never ducked a question, no matter how tough. Delivering satisfactory answers under stress is one skill she honed early.

Back then she had just moved into a new position at Citi. An important business account-News Corp.-was going through a liquidity crisis, and Citi put Alemany in its World Corporation Group to handle the account.

That ruffled Guenther Greiner, who founded the group and still ran it at the time. He prided himself on picking every employee personally. He immediately summoned Alemany to his office. "He was saying, 'If you lose a cent-we've never lost any money in this group-you will be fired.'"

He followed up the harsh welcome with monthly meetings. "I'm telling you, it was like a test. That morning on the train to work, instead of reading the newspaper, I would have all my notes, preparing for the meeting."

Though she dreaded those mornings, in retrospect she sees the wisdom of his approach.

To this day, she still gets phone calls from Greiner, who is retired. But now he says how proud he is of her.

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