If you're looking for excuses for not pursuing your dream, just count the candles on your birthday cake. Of course, there will always be plenty of reasons for not following through. But ask successful entrepreneurs what's the right age for launching a business, and they'll say: right now.

Your age (whatever it is) can work in your favor, says Jean Biri, author of a blog on early stage entrepreneurship. "It's never too early. Youth allows mental flexibility and a fresh perspective," says Biri, whose small-business consultancy, Groupe Bire, advises small businesses on strategy, marketing and branding. "And it's never too late. Mature self-starters have an edge in minimizing risk and in being taken seriously by investors, lenders, customers and other stakeholders who value experience."

Still scared? Good. "Fear, anxiety and stress are universal to all ages. I don't believe a business can survive without them," says Don Bracken, author of Career of Gold, a primer for starting a new business or career after age 50. He should know. Now 70, Bracken recently launched his own company, History Publishing.

"Fear of the unknown is natural. If you don't have that, your emotional system is on the blink. Dealing with it is a question of courage, confidence, acceptance of what life throws at you and the willingness to deal with it," Bracken says. "Anxiety is necessary to compete. And stress—well, without it, not much is happening."

Too young? No such thing. Too old? What's that? Just ask these entrepreneurs.

'No One Takes Me Seriously'
"My biggest fear was not being taken seriously," says Elizabeth Frank, who was 24 when she launched her New York City event-marketing firm, Eye5. "Potential clients felt they had the right to ask my age, or say my business is 'so cute!' " So she took her photo off her online bio and used her masculine-sounding last name.

She also made a point to always appear ultraprofessional. "I'm careful about my wardrobe, my e-mails and every aspect of running my firm," she says. "Most difficult was interacting with employees—who were often older than I was. I had the challenge of presenting myself in a managerial role without alienating my team. With the help of a crash course in interpersonal relations, I mastered the technique of conveying the same respect for my staff as I do for clients."

After almost seven years, Frank's age is no longer an issue. With revenue doubling each year for the first four years, her firm has grown to six cities. "The first half of 2008 has been our largest-grossing yet," she says.

Anne-Marie Faiola launched her soap-making business, Bramble Berry, out of her living room in 1998 when she was 20 years old. From the get-go, she took her company seriously—even going back to school for an MBA for formal business training. But vendors often joked about her company as merely a phase. Well, you know what they say about sticks and stones.... "I combated their stereotypes with hard numbers," Faiola says.

Her greater challenge was lack of capital. "Bankers treated me like a little girl who was playing business—even after I had grossed my first $1 million," she says. "But that turned into a blessing because we have been self-funded, debt-free and profitable for 11 years. I was forced to grow my company slowly, through cash flow from operations rather than do the traditional big loan, long payback."

Today, with more than 2,500 products, Bramble Berry has a nationwide customer base, plus a retail store, Otion, in Bellingham, Wash. Annual sales top $4 million.

'I Don't Have the Energy Anymore'
After 21 years as a financial writer for the Dallas Morning News, Scott Burns was offered a buyout that would have allowed him to settle into a leisurely retirement, with ample time to scribe the occasional book. But the idea for an Internet-based investment business kept buzzing in his head.

At first, he worried about the rigors of entrepreneurship. "I'm healthy and energetic," he says, "but I don't have the reserves I had at 40 or 45. My fear was that I would not be able to keep a balance between the new business demands and a personal life."

But the more he thought about it, the more he wanted to take the plunge. "The attraction of starting an investment-advisor firm was enormous," he says. So a few months shy of his 66th birthday, he launched AssetBuilder. Within two years, the company secured more than $125 million in business from 300 clients in 24 states.

"Yes, it's a massive commitment of time and energy, but it's an entirely reasonable thing to do since I never learned to play golf," he jokes. "Being engaged this way is far better than being disengaged."

One thing he's learned over the years is that one person shouldn't—can't—run a business alone. "It helps that we've built a great team," Burns says. "Many younger people have the illusion that they can do everything themselves, but 'silver entrepreneurs' know that teamwork is necessary to grow a business."

A few decades ago, Burns thought his 67th year would be 'a placid time,' he says. It's turned out to be anything but that. "Those closest to me say I look healthier and happier since my 'retirement' from a major corporation," he says. "I am."

'I'll Go Broke!'
Entrepreneurs of all ages share the fear of financial failure. Twenty-somethings fret about debt or losing their chance at a high-paying corporate career; older entrepreneurs lose sleep at the prospect of seeing their nest egg disappear.

Kevin Beardsley was barely of drinking age when he had the idea of bringing Cachaça, a smooth rum made from sugar cane, from Brazil to the United States. He recruited Steve Diforio as his business partner, and together they created Beija Cachaça, incorporating the company in 2006. They were both 22.

Bankers didn't exactly jump on board behind the college-aged duo with a dream and a drink. "We bootstrapped our operation by working night jobs," Beardsley says. "We maxed out our credit cards and flew to Brazil to meet suppliers. We each had several thousand dollars of high-interest debt hanging over our heads. We were literally all in."

But the partners stayed focused. "We broke down the big picture into smaller goals and tackled them one by one," Beardsley says. "We set timelines. Accomplishing each step boosted our confidence."

Beija is already a hit in Boston's trendiest, elite bars. "The first seven months after our launch, we sold 392 cases (2,352 bottles)" an incredible number for a new brand, especially since 90 percent of our sales are re-orders," Beardsley says. Beija is now also sold in Connecticut, and the company will expand operations to New York in the coming months and other markets next year.

That's Too Big of a Risk
Money was also Quency Phillips' biggest worry. At 28, he was earning an enviable salary as a senior account executive for a pharmaceutical ad agency, but he longed to strike out on his own. But as the primary breadwinner for his family—mother, siblings and their kids—he was afraid to lose that paycheck. "I was a poor kid from Chicago's South Side, and I never wanted to face poverty again," he says.

Then a friend reminded him of past job offers he'd received. "The realization that I could always secure a position gave me the confidence to make the leap," he says. In 2006, Phillips launched Fuzion, a New York City-based marketing and artist /athlete-management agency, which posted revenue of $1 million last year.

But if relinquishing future wages is daunting, think how much scarier it is to risk hard-earned life savings. Older entrepreneurs lose sleep at the prospect of seeing their retirement funds vanish.

I Can't Grow That Fast
"When you're 25, you think you can't fail—but if you do, you have 50 years to recover," says Naomi Fenlin, who at 50 opened Cosmopolitan Skin Care Studio in Philadelphia, which specializes in treating adult acne, aging and scarring. "But I only have 15 working years left in me. If I didn't do it right on the first try, I'd be honoring my debts with my retirement fund. That's scary, especially because in your 50s you also have a family and all the obligations that come with that."

Fenlin decided to limit her risk by making purchases in small, thoughtful steps. "In my business, there's a laser for every body part, every wrinkle, every pimple and every scar," she says. "Each one comes with an enormous price tag. So, rather than filling my office with all the equipment at once—like I would have done if I was 25—I let my patients drive every purchase. Before every equipment investment, I asked myself, 'Does my patient base need it, or is this procedure just a fad?' "

Thanks to her patient-focused philosophy and careful financial decisions, Fenlin has been in the black since she opened her doors in 2007, and her business has grown to 100 patients.

Bracken, the septuagenarian who launched a publishing company two years ago, admits he faced similar qualms. "The fear of losing one's retirement fund strikes at the very heart of one's security. Those negative emotions certainly battled it out in my inner depths," he says. "I had to kick-in the positive emotions of gain, focus and belief."

He tallied what he had going for himself: a lifetime of experience and business contacts, finely honed decision-making skills, better judgment than when he was younger and the opportunity to do something meaningful. With that perspective, his worries subsided.

"When I was in college, I intended to go into publishing, but life got in the way," he says. "Now the roadway is clear for this chapter in my life. I've a 20-year plan for developing History Publishing—and have factored in early retirement at age 90. When I am 91, I will miss it."