Unusually high energy levels and working long hours are hallmarks of most entrepreneurs.

But we’re not talking workaholics here. Workaholics, who don’t know how to take a break, end up burning out. Entrepreneurs work extraordinarily hard, but in spurts or for reasonably defined periods to achieve specific objectives.

It’s just that their spurts or reasonably defined periods are often longer than the average non-entrepreneurial person could tolerate.

To create the business empire—whatever that definition might be to the individual—or to keep it afloat when the business hits a storm, entrepreneurs routinely work hours that seem ungodly long to others.

Entrepreneurs also forego the leisure time and vacations others take for granted. And they’re willing to put in the long hours because their focus is on the greater goal.

That’s what Catrice Austin did to build VIP Smiles, her now five-year-old cosmetic, general and sports dental practice in New York City.

Austin decided to go on her own after realizing that the starting pay for new dentists in a dental practice was rock-bottom low. Even taking temporary jobs as a dental hygienist, she earned more than she did as a dentist. “That was so disturbing to me,” she remembers.

So she shared office space with another young dentist, worked extra hours as a school dentist for two years to make ends meet, and spent endless hours networking with business, entertainment and sports organizations.

The result of years of sacrifice is a thriving practice that includes major entertainment and sports celebrities among her patients.

Would she work for someone else again? Not a chance. “The ability to make my own decisions and have control of my destiny has been priceless, especially in these trying times,” she says.

Her attitude is like Tom Antion’s, who owned several other businesses before his current incarnation advising small-business owners on Internet marketing “I am like a bulldozer,” says Antion. “I will go until the job is done.”