(FORTUNE Magazine) – Shelly Lazarus, chairman and CEO, Ogilvy & Mather Worldwide: "When I was 22, I was an intern at General Foods. It was during the Vietnam war, and the assistant and the associate product managers went into the Reserves. So never having worked before, I took over the jobs of two men. I would write down all the vocab and things I didn't understand and go over them with my boss. Each day I filled up less of the yellow pad. If you have enough energy, you can do anything, and you don't have to do it all yourself. Just find the right person and ask questions."

David Stern, commissioner of the National Basketball Association: "My dad owned Stern's Delicatessen in Manhattan. I mopped, packed, did whatever you had to do to keep it running. The worst part was trying to meet my father's standards."

Ben Stein, host of Win Ben Stein's Money: "It was a summer job when I was 15, at Shoe Giant in Langley Park. Maryland was very segregated, and a lot of black people came to the store. I found them incredibly pleasant and easy to do business with. They didn't have the suspicious, crazy attitude of the white customers. And this is really what started me--I know this sounds strange--on the road to being active in civil rights."

Donald Trump: "I graduated from the Wharton School of Finance on a Saturday, and Monday morning I was working for my father in Brooklyn. I was very familiar with construction through my father, but this was a hardhat job and I was supervising the different trades. I was very proud of that. I got it built on time and under budget, which I've done numerous times since."

Richard Scrushy, chairman, CEO, and founder of HealthSouth Corp.: "My first job was at Thirsty Boy Milkshakes. This was when I was 8 or 9--back then they didn't have the child labor laws they have now. When I was older, I worked for a brick mason. Laying brick makes everything I have ever done in my life look easy. That's when I decided to go to school, because physical labor was so hard."

--Grainger David