From the April 2008 issue of Entrepreneur

Robin D. Richards used to dig through his daughter's backpack because he never knew when he'd find vital information from school buried in there on crumpled fliers.

There must be a better way for schools to communicate with parents, he thought. When he received a call from the school principal inviting parents to back-to-school night, he saw a business opportunity.

It wasn't the first time Richards, 50, recognized a need and profited. He's part of a rising trend: serial entrepreneurs who start, grow and sell companies. In 2004, the backpack brainstorm led Richards to start The NTI Group Inc. in Sherman Oaks, California, which works with schools and government agencies to send mass voice messages, text messages and e-mails. Richards just sold the company for a whopping $182 million. Before that, he was founding president of MP3.com. Earlier, he started a teleservices and database management company.

Serial entrepreneurship has become a cool model for doing business, says Julie Lenzer Kirk, a business consultant who teaches at the University of Maryland, Baltimore County. "The type of person who does the startup is not necessarily the type of person who wants to manage a $10 million company."

Wanting to sell the business is far more common, says Dan Steppe, director of The Wolff Center for Entrepreneurship at the University of Houston. "That's the model we teach."

It's not just cachet that motivates serial entrepreneurs. Some decide to sell and start over because their endeavors are no longer satisfying. Jen Groover co-owned a wellness center when she became seriously ill. That gave her time to reflect on what she loved about her business and what she did not. She decided to phase out of the fitness industry in 2000 to launch Jen Groover Productions. The Broomall, Pennsylvania, company has several dozen products in various stages of development--including handbags and children's clothing--and has signed a brand licensing deal. "Every day now, I feel like I'm going to play," says the 35-year-old. "There's so much happiness and reward, it outweighs any stress."

Groover's experience proves that your next venture doesn't need to be related to the first. If you've spent years in software, you may wonder how you could develop snack foods without expertise in the industry. The answer is to hire experts who intimately know the field you want to be in. "The industry knowledge is critical, but it doesn't have to come from you," says Kirk, herself a serial entrepreneur in--no joke--software and snacks.

Once you decide to sell, you may experience a surge of creativity for identifying new entrepreneurial possibilities. "You put that filter on," says Kirk. "You don't even have to have that killer idea yourself. You can leverage someone else's research."

Starting something new is easier if you have solid colleagues behind you. Richards has four executives in finance, marketing and sales who have moved with him from one company to another. He shares the wealth: "When you sell, if your teammates all share a piece of that, it's easy to retain teammates."

Richards also recognizes the need to keep improving the quality of management and staff. For him, that has meant asking some employees to change roles. Misplaced allegiance can lead to problems, he says. "[Some people] recognize their teammates aren't as good as they need to be, but they stick with them. They think that's loyal, and I think that's disloyal. Your obligation as a leader is to the whole."

Part of being a leader is knowing how much failure to allow yourself. "I have more fear of regret than I have of failure," Groover says. Steppe, who's started, managed and sold five corporations, believes the fundamentals of success are the same for any enterprise: Move from observation to idea to feasibility study, then to organizing the business, designing the product or service and raising capital. Knowing when to leave is crucial to the process. It's obvious it's time to go when you've lost passion for the work, but Steppe also advises having candid talks with your mentors. People you trust can provide insight about when to sell.

Some serial entrepreneurs find that the challenge isn't to keep the ideas coming, but believing you can be successful in more than one area. "Somewhere, somebody said you become an expert at one thing. I disagree," says Groover. "If you've done all you want to do with a company after three years and want to sell it, you're doing the best thing for yourself."