BCG, as it is known, works with big companies like Starbucks, GlaxoSmithKline and Shell, pushing them deeper into the digital age. And for the last eight years, BCG, which is private, has been led by Rich Lesser. Mr. Lesser, who has been with the firm since 1988, will step down next month.

Much changed during his tenure. For the first few years, Mr. Lesser mostly found himself counseling other executives about changes in technology, analytics and other ho-hum business issues. Then, with the arrival of the Trump presidency, corporate leaders were thrust into the political and social debates like never before, and BCG was helping clients navigate the culture wars.

“The divisions in our country continue to grow and grow, and sometimes you think they might be turning around, but I don’t think we’ve really seen that yet,” Mr. Lesser said. “And in a number of cases, there have been policies which then created more of an imperative for C.E.O.s to speak out.”

Just as the Trump presidency was winding down, the pandemic hit, and today BCG’s remit has expanded to climate change, Covid-19 and more.

This interview was condensed and edited for clarity.

What was your childhood like?

I grew up in Pittsburgh, and the city itself was very influential because there were only two aspects of Pittsburgh in the ’70s. It was under enormous stress. It was dealing with adversity, thousands of jobs lost and steel mills shutting down. And at the exact same time you had this adversity, you had the Steelers, and there was this winning-team mentality.

My mom was a teacher, and we spent dinners talking about how do you motivate kids, how do you create an environment of high achievement? And my dad was the C.F.O. of these little retailers. He had very strong values but was always under stress. I used to shine shoes, and we had this discussion when I was 14 about paying taxes, and how nobody reported their tips. So I started filling out 1040 forms, reporting my tips and paying taxes on it, because that’s just what you did.

Was there one engagement or client you had early in your career that made a big impact on you?

We did work with a telecom during my first 18 months, and we disagreed fundamentally with one of the senior leaders at the company, who insisted that we not tell his boss our view that their business was declining faster than they realized. He was really almost threatening the partner not to say that. And the partner said, “We’re going to say what we believe.” To a first-year consultant it was this moment of high drama, to go in and watch the partner say what he thought. The senior leader at the company was very angry, but it was the right thing to do. And in the end, the most senior client really appreciated someone putting bad news on the table in a very direct way.

How do you think the pandemic has changed business in ways that will endure in the years ahead?

From the very beginning, we have used the phrase “new reality,” not “new normal.” “New normal” implies a return to the way things were, maybe with minor tweaks. “New reality” implies a different environment. My continued belief is that it will take longer than we would like, but eventually this will be seen as more endemic than pandemic. It’s not going away, but we’ll learn to manage.

Companies have realized that there are things that have changed in a permanent sense: the way consumers and workers live their lives. Their expectations. Digital, which was already on the acceleration path before the pandemic, just jumped to a different curve.

People are looking for more flexibility and different models of collaboration. And I think that’s a fundamental change. Most C.E.O.s are saying we underestimated the capacity to change the way we work. BCG was very focused on being innovative in what we do, but taking for granted that this is how the work gets done.

What were the common characteristics of the C.E.O.s who managed to do well over the past year and a half?

The ability to learn very rapidly, and not just consume knowledge, but to translate that into experimentation and action. A purpose-driven, authentic style. Empathy, for sure. And a high orientation to adaptiveness and agility. Leaders who combined those four things have really stood out.