A trend I am seeing increasingly is what I dub the "on-again off-again entrepreneur."The on-again off-again entrepreneur is someone who moves back and forth between being employed and owning his or her own business -- multiple times. It's not an either/or question: either being an entrepreneur your whole life, or being employed your whole life. More frequently these days, people are doing both at various times, moving in and out of entrepreneurship as the exigencies of earning a living force their hands.Jory Des Jardins, a lovely person who I met at the New Communications Forum in January, writes frequently about this phenomenon. In a well-written piece from February, she talks about entering self-employment again for the third time. She then meets up with an old friend who has left his own startup business to return to the corporate world again. His comments give insight into why some people become on-again off-again entrepreneurs:He parked in front of my place wearing jeans and a button-down silk shirt--a dead giveaway that he was working a corporate job again.He was almost sheepish when he came inside, explaining why he was in my neck of the woods."We had a training out here for my new job. Don't worry, it's only temporary."We walked to a coffee shop and shared a cookie, like we used to. He seemed happy, if not cautious. He liked being married, he said, though he wasn't sure about the new job."What's wrong with it?" I said."Nothing, except that it's a job. A regular old job. I'm back in a cubicle, making phone calls and enduring a commute. I said I would never do that again. But I'm married now, and she's just out of grad school and not working yet." He pulled out a business card."What's this?""It's the company I'm starting on the side. If everything works out I'll be back working at home and running a business from my laptop.""That sounds nice.""I can't do this nine-to-five thing knowing that's it. That this is how I'm going to be living my life."This describes one type of on-again off-again entrepreneur: the entrepreneur at heart who takes a corporate job because of needing the money. But he doesn't like it...not one bit. He's just biding his time until he can sustain himself in his own startup business and get back to working from a laptop at home.It may take several tries, and several bouts of corporate employment, before he gets it right. But the on-again off-again entrepreneur will keep trying.There are other reasons for being an on-again off-again entrepreneur. I'll talk about some of those reasons in future posts.