HALF OF THE COMPANIES ON THIS year's Fast Track opened shop after 1993. More than one-fifth have started since 2000. That means many of the fastest-growing home building companies have known only good—or great—times.

That's changing. In many parts of the country, traffic and sales are slowing. Both public and private companies are revising their projections for 2006 and 2007 downward, and some already are selling land and laying off employees to curtail costs.

It's times like these when experience counts. Even among recent startups, many executives of the companies on this year's list can boast of decades in the industry, often spent in the offices of the largest national builders. Few were CEOs during the bust of the late 1980s and early 1990s, but they learned important lessons about what to do—and what to avoid—while heading construction, sales, and land operations. They paid their dues, climbed the corporate ladder, and sometimes even tripped on their way to becoming their own boss.

These entrepreneurs know 2004 and 2005 might have been aberrations, and many seem prepared for a downturn. Their plans for surviving, and even thriving, through a rough patch resemble what they did to leap on to the Fast Track in the first place, minus buyer frenzy and outrageous price appreciation. They say they're exercising caution on land deals, reining in overhead, and adjusting pricing and product to appeal to a wider cross section of buyers. If the industry instinct that's served them well for so many years holds true, next year's Fast Track may be slightly less speedy, but just as solid.

PERFECT PITCH Ken Richardson Owner and Senior Partner Richardson Homes

YEARS AS A VICE PRESIDENT OF sales and marketing for candy companies soured Ken Richardson on the corporate rat race. So, in 1983, he turned down his employer's request that he relocate from his home in Oklahoma City to the corporate headquarters in Chicago, and with no prior home building experience, he decided to become a custom home builder. He spent four months driving his pickup truck through new-home communities, stopping to ask contractors about the building process.

He ventured into home building debt free, which made trading his $80,000 salary for $9,400 his first year in business easier. His business plan—which included building at least 20 homes a year from the outset—hinged on providing higher quality at lower prices than his competitors. (To this day, his homes are as much as $30 per square foot cheaper than those of nearby custom builders.)

Despite his building-free background, Richardson was optimistic he'd succeed. “I'm a professional when it comes to sales and marketing,” he says. “If you can sell the homes at a profitable price, you can grow.” With the aid of strong employees and subcontractors, Richardson hit his goal by his fifth year in business, when he closed 25 homes. In 2005, his company built 63 custom homes, half of which Richardson categorizes as “executive homes,” with more than 3,500 square feet.

Richardson credits much of the company's recent growth on a new sales and marketing strategy: television advertising. In 2004, he began pouring $300,000 annually into the ads, which reach the entire Oklahoma City metro area during the morning newscast. Though Richardson expects to close roughly the same number of homes this year as last, the geographic reach he's gained through the ads has helped him build a safety net if a slowdown appears. “If building drops in half, I'm getting my share out of the whole Oklahoma City area,” he asserts. “If you build in two developments and they're dead, you're out of business. I may need to cut back, but I'll survive.”

ENTREPRENEURIAL SPIRIT Michael Gaffney President Gaffney Homes