Oprah Winfrey rose from poverty in rural Mississippi to become host of her own talk show, the head of a huge media company, and the most powerful woman in entertainment. Worth about $1.4 billion, she has built her career on instinct and the counsel of friends, including poet Maya Angelou, musician Quincy Jones, and actors Bill Cosby and Sidney Poitier. Along the way, she has tackled social causes both on the air and off. Winfrey recently spoke at her Chicago studios with U.S. News 's David LaGesse.

Your voice gives you a unique place--your combination of business leader and entertainer. How does that shape your role?

I see it more as a calling. We live in a society that doesn't pay attention to you unless you have money or fame . . . . The responsibility of people who have money and fame and some kind of clout is to use that in a meaningful way. There is also responsibility for me to always be thoughtful and never flippant.

Does that stifle you?

No. It's actually more stimulating because it means . . . you have to go to a deeper place where nothing is coming from just off the top of your head.

You have mentioned Bill Cosby as one who was helpful to you in organizing your career.

Bill Cosby was famous not only for what he was doing with the Cosby Show-- the groundbreaking, innovative way he was showing black families--but also because he was making multimultimillions of dollars a year. [He was] the first and only black person who you had ever heard of to make that kind of money while handling it with such grace. He gave me advice that lives with me to this day about signing your own checks, and I still do sign most of them. Obviously, I could afford any bills that I acquire, but you need to know what your phone and electric bills are.

And you know what your phone and electric bills are?

Yes; they're too damn high, I can tell you that.

You once took pride in never having taken a business course or read a business book.

That was a mistake--I should have read some.

Why? Did you make classic business errors?

Classic, classic. I started out this company--there were five of us--thinking you could run a business like you run a family. The classic mistake was not understanding the need for systems and infrastructure. There has to be a system of communication because everybody doesn't operate the way you do. People handle power differently, and it means to other people what it doesn't mean to me.

Do you have a weakness as a leader?

[Avoiding] confrontation is a weakness. So I have to shore myself up with people who can [be confrontational]. I'm also not good at the great idea; I'm good at building on the great idea.

How has being a woman formed your leadership style?