Do you have it?

You come from a line of people who couldn't work for someone else. I don't mean that in a negative way. People who are successful at establishing their own business tend to have had parents who worked for themselves. It's usually easier to get a job with a company than to start your own business; people who strike out on their own often have the direct example of a parent to look to.

You're a rubbish employee. No need to sugar-coat this one. People who start their own businesses tend to have been fired from or quit more than one job. I'm not saying you were laid off for lack of work or moved from one job to a better-paying one. You were asked to leave, or you quit before they could fire you. Think of it as the marketplace telling you that the only person who can effectively motivate and manage you is yourself.

You see more than one definition of "job security." I am truly envious of the few people I know who have stayed with one employer for 25 or 30 years. They look very secure. But how many people do you know who are able to stay with one company for that long? In a rapidly changing economy, job security can be frighteningly fleeting.

You've gone as far as you can go, or you're not going anywhere at all. Sometimes the motivation to start a new venture comes from having reached the top of the pile where you are, looking around, and saying, "What's next?" Early success can be wonderful, but early retirement can sometimes drive energetic and motivated people totally crazy.

You've done the market research already. Don't even talk to me about your great business idea if you haven't put the time into figuring out if there's a market for your product or service. As the people behind any number of failed Internet ventures will tell you, "cool" doesn't necessarily translate into "profitable." Don't bother building it if you haven't figured out whether there's a good chance the customers will come.

You've got the support of your family. Starting a business is stressful under the best of circumstances. Trying to do it without the support of your spouse or other significant family members or friends would probably be unbearable.

You know you cannot do it alone. You might excel at promoting a business. Maybe you love running the financial end of the enterprise. You could be someone who starts a business because you have unique creative or technical know-how to create a product.

Fancy becoming a dot.com entrepreneur? New Office Live lets you create a professional-looking website with your domain name and up to 50 email accounts, free of charge.

Dan Germain and his three university friends Rich, Adam and John certainly had what it took to be entrepreneurs. They left their jobs to set up a smoothie company. Read how they started innocent drinks.

Celebrity activist Bob Geldof is also an entrepreneur. Read how he started a company.

Nearly 70,000 people in the UK are making a living by selling goods on eBay. You can join the growing number of eBay entrepreneurs, as Emma Jones explains.

Vicky Mitchell gave up her senior job in the City to sell funky walking sticks. Read everywoman's account of how she and Kerrie Keeling realised their business dreams.

Richard Davies made the transition from fishing guide to internet entrepreneur, when he started an online business selling beef jerky from the Hebrides.