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Mark Lewis, 48
Then: Software developer
Now: President of the company

Reinventions come in sizes big and small, and sometimes the hardest moves are rank changes within the same company.

Since 1999, Mark Lewis has been working at Lexington, Ky.-based Tenmast, a company that provides software to government housing authorities. He was putting his tech background to use as a software development manager, but he wasn't satisfied.

"I was frustrated," he says. "My boss came to me and said I seemed unhappy, and was letting my frustration show."

In 2007, Lewis reexamined his goals. "I began communicating differently to my coworkers. Working through the problems of a business became a passion."

His colleagues took note. Lewis' boss observed that he might be happier in an upper-level management position, and together they prepared him for a move into the president position, just below the CEO.

Before, Lewis managed nine people. Now, as president of Tenmast, he oversees 70. But the number of people under his watch is not all that has changed.

"When I was in the development position, my problem-solving opportunities were directed toward computers. I never applied that to people. I now have all the senior managers reporting to me, and I do all the budgeting and envisioning for the company. It's a completely different role."

In 2010, the first year of his presidency, Tenmast exceeded its budget plan. Lewis says that success is wonderful, but being happy at work is even better. "The satisfaction level of my job is completely different now."

NEXT: Amelia Heape, 40
Last updated February 07 2011: 5:38 PM ET
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