On Monday, Cathy Engelbert made history. As the next CEO of professional services firm Deloitte, Engelbert will become the first female U.S. CEO of a “Big Four” firm. Formerly chairman and CEO of the audit subsidiary of Deloitte, Engelbert joined the company in 1986. She will be in charge of will take charge of the company’s 65,000 employees and $15 billion in annual revenue.

Fortune caught up with her to hear about her plans for the future and her thoughts on leadership.

Edited excerpts:

What’s it like to be the first to achieve something?

It is a proud moment and a milestone. To the extent that I can be a role model for diverse leaders at Deloitte, I love it. This is a tangible demonstration of our commitment at Deloitte to the advancement of women. I have gotten so many emails today from our women — and men — who really believe that we have an inclusive culture as proven through my election.

Why is it important for women lower down the pipeline to see leaders like yourself on top?

Women and minorities account for about 66% of our new hires, so we clearly want to make sure that our inclusive culture is developing them into leaders and be successors to our top leaders. As you think about the workforce of the future, women and minorities are such an important part of that future. I see it in our clients as well: There are more women in the C-Suite and in the boardroom. I know, as The Broadsheet talks about, we are not where we need to be and we have a lot of work to do, but I am really optimistic.

What has Deloitte done to ensure an inclusive culture?

We always strive to pick the best person for the job regardless of gender or ethnicity, but in order to ensure that our women and minorities are advancing, it is about sponsorship. It is about those partners that sat in that room and when an opportunity came up for a capability that I wasn’t strong in, offering me the role. That is the culture at Deloitte: To make sure we are all maximizing the capabilities that we have.

You joined Deloitte in 1986. What is the single biggest change you’ve seen within the company?

Our businesses have changed over that time because our clients have changed. We need to match up with how our clients have evolved. I come from a family of eight children. I had five brothers, and I went to a male-dominated university [Lehigh University.] Back in 1986, the public accounting profession was very male-dominated. As I think about the change, we have evolved enormously and [the number of] women in leadership ranks are up considerably. I am proud of that and part of that now.

If you could only ask one question of a job candidate, what would it be?

I like to ask what they think the Fortune 500 will look five to ten years from now. My favorite question is around that pace of change and really being a futurist and asking people questions about what they see their business evolving to in the future.

What’s the best advice you ever received?

To take some risks in my career and do some different things. I wouldn’t be a CEO today if I didn’t do different things to build capabilities and build experiences because to come a leader you need varied experiences. So the people throughout my career who said, “Don’t stand still, take risks and take on new responsibilities and opportunities,” they were absolutely right.

 

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