It’s a note from her three boys from 2008 when Porat was working around the clock to help the Federal Reserve save American International Group, the giant insurance company whose imminent failure threatened to nuke an already crashing global economy.

“On one of those nights where we were working through the night, I came home and my three boys left me a little note because they knew I’d at least come home and shower,” Porat recalled in an interview. Though she didn’t say what exactly her boys wrote, she added “in their own words, three different personalities underscored how very proud they were and how important they thought the work was.”

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Porat, often called “the most powerful woman on Wall Street,” viewed it as a triumph of her career-long approach to “work-life balance,” a phrase she abhors. “It was really sweet because it said to me, ‘They get it.’ They’re proud … and they have been integrated into Morgan Stanley throughout their lives.”

Instead of “balance” — something she says sets women (and increasingly men) up to fail — Porat encourages employees to find a satisfying “mix” of family and work in their lives. The mix will shift depending on needs in both places, but the two should never be fully isolated from each other.

Porat grew up in northern England, Cambridge, Massachusetts, and Palo Alto, California, the daughter of a research engineer father and psychologist mother. There was never any question that she would have both a family and a major career.

After undergrad at Stanford and a pair of master’s degrees, Porat, 57, entered Morgan Stanley in 1987 and quickly became a mergers-and-acquisitions whiz before leaving for Smith Barney in 1993.

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It was a rare career misstep for Porat, who immediately realized she wanted to return to Morgan Stanley, which she did in 1996 going on to head a pair of investment banking teams before becoming chief financial officer in 2010.

In her current role, Porat, alongside Morgan Stanley Chief Executive James Gorman, has retooled the blue chip bank’s business mix into a more stable, post-crisis franchise that is in many ways now the envy of Wall Street.

Why aren’t there more women in senior positions of power, including CEOs, on Wall Street? If there were, would some of the meltdowns not have happened?

When I started there were very few women at the managing director level and very few who had families, which is something that was important to me. So it’s not like when I looked up I could say, “Well, that’s who I want to be.” And you see this real narrowing of a lot of women opting out of the profession as they ascend up the ranks, which I think is really unfortunate. Since 1987, there are now many more of us as at the higher levels with families, so I think as role models we are encouraging more women to stay within banking and rise up through the ranks.

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I think what Sheryl Sandberg said about the importance of “leaning in” is very true but it’s not sufficient. Because if you are leaning in to a door that is nailed shut, you are just going to get bloodied and tired of trying to push that door open. So you have got to have the next level, which is, “how do you open up those doors to the ever-bigger roles?”

The second point you make is intriguing. Would ’08 have been different had there been different voices around the table? And I think one thing that is encouraging to me is the increase in data that suggest that organizations with a higher percentage of women in the C-suite or boards with a greater number of women or other under-represented minorities are more effective and have greater financial results.

Did going into the male-dominated, testosterone-fueled world of Wall Street give you pause?

There were enough times even coming up to that point where I was one of very few women. I remember the first time it struck me is I was an econ major at Stanford as an undergrad, and it struck me how few women were econ majors back in the ’70s. And then in business school how few women. … And even then I thought, gosh this is really unfortunate. So when I started here, what was very different was that there were very few women at senior levels, period, and very few that had a family.

There were certain things along the way where being a woman was actually intriguingly helpful … When I was a very young associate, I was asked by a managing director to present to a board of directors. … At the time, the CEO had said they needed more women in the boardroom and part of the reason was that they had an R&D focus that was actually pretty nonsensical because it was run by men. … They were having problems with their product development because they didn’t have enough women at the senior-most ranks who could provide an overlay that was quite relevant for their customer base.”

You mention seven sponsors who helped you along the way. Were any of them women?

They were all men. … The reason they weren’t women was because there weren’t women who were running important parts of the business who then had the authority to open those doors. And so to me a sponsor is someone who takes a risk on you, gives you a real stretch goal, a real stretch opportunity, backs you up when you need help. It wasn’t that I was choosing not to have women as sponsors. It’s just that there really weren’t women running parts of the business.

Women weren’t as collaborative and I think mutually supportive as they are now. … You just didn’t do that. And when I was coming up through the ranks, running small businesses, I felt it was important to do and it was part of coaching and training women as they came up through the ranks. And the guys would always make comments about it so it would be uncomfortable. And I would say, “You know, you guys do this with each other basically every day so just chill on it.” Women are playing more of that role now.

Is it harder for women to “pivot” from one career moment to another or to pivot away from a mistake?

It is harder for women to do the pivot in part because you are not one of many to begin with. … When I left and went to Smith Barney with Bob Greenhill, I was very quickly of the view that the place was not what I was accustomed to. … And I did feel that I screwed up my career. And then when I did have the opportunity to come back I was thrilled to come back. … There are fewer in the senior positions, it’s somewhat in many respects lonelier as a result.

And without clear guidance, feedback, which I think sometimes it’s harder for men to give women because they are concerned what the reaction will be, it’s tougher for women to move on and there is more self-flagellation. … And it is beautiful to be able to just move on to the next one and view a mistake as a great learning opportunity. I wish I could say I was great at that.

What are the most important pieces of advice you would give to a woman just entering a big Wall Street firm or any other big company?

Don’t defer the rest of your life to a later time. You have got to find a mix. And I find it so tragic when women think they need to put the other part of their life on hold to a later date so they can have accomplished something professionally because I think it could lead to one of two very bad outcomes. One is you never get to that other part of your life, which is really unfortunate and for me would not be fulfilling.

Or you end up in this tension that I talked about previously and therefore you go the other direction and feel the only way to get that other part of your life where you want it is to leave what you are doing professionally. And in my view, going back to my mom who was my first sponsor, maybe my first and only female sponsor, but she was an incredible model. Because we had a really close family and she worked. Those are the main messages.

Do you feel you’ve served as a role model for your kids in the way that your mom served as a role model for you?

The answer is yes. But you prompted something else in your question. Because my dad was also an amazing sponsor because he was gender blind. He didn’t treat my brother any differently than he did me. His assumption was, because he’s a physicist, a research engineer, his assumption was of course I should be great at math and go off and be whatever I wanted to be and he was amazing. So I have three boys and I often ask them that question because I’m so often asked the question, “How can you be a good mom if you work so hard?” And so I often ask them and I think they are tired of hearing the question at this point. And we are very close. And we are still close and they are teenagers, so I think that’s a great sign. They are proud.