It was 1979, and an enterprising, 23-year-old Charles Githler was in a sticky situation. He was more than two hours late for a critical meeting with the manager of two hotels in Miami's Coconut Grove. The founder of a fledgling investment-seminar company called Intercontinental Conferences, Githler had been rushing from one Miami hotel to the next all day, trying to find enough rooms for the unexpected number of people who had signed up to listen to the impressive financial experts he had lined up. The Miami event could be a breakthrough for his young company, but he needed to find rooms for his customers.

After waiting two hours, 21-year-old Kim Van Dyne, the smart and ambitious manager of those two hotels, was not in an accommodating mood. She decided to go home, where she'd already changed out of her work clothes when the hotel called at 8:30 p.m. and said that a Charles Githler wanted to see her. "So I got redressed, called him and said, 'OK, I'll pick you up at the Omni,'" she recalls. Then she added somewhat intimidatingly, "'I'll be the blonde in the white Corvette.'"

The pair roared off to a restaurant, where she ordered a club soda with lime, he ordered a double scotch, and they hammered out a contract for a block of rooms. "It wasn't the best deal I'd ever copped," Charles admits with a laugh today.

Maybe the contract didn't work out so well for him at the time, but the deal led to an almost 30-year love affair (they've been married 24 years) and a business partnership so close and so balanced that the couple has managed to weather two near-bankruptcies, adapt to roller-coaster changes in the investment market and grow their Sarasota-based InterShow from a faltering start-up to the largest investment-seminar business in the world.

Most residents of Sarasota are unaware of the company. It doesn't advertise locally, and aside from Wall Street Live, the Sarasota investment show the Githlers put on to raise funds for local charities, InterShow is invisible-although it's located in downtown Sarasota, on Palm Avenue. Charles is the more public of the two, affable, down to earth and outgoing, often involved in leadership positions in the local business community. Kim describes him as a Harry Potter type, a good-hearted guy in glasses who's idealistic and visionary. Ultra-organized Kim, with her fluffy halo of blond hair, is publicity-shy and extremely private, although her compassion for children in need is well-known to local charitable organizations. The couple are more recognized for their philanthropy, their mansion on Sarasota Bay, and their local condo and hotel projects than as the operators behind a $25 million global business.

But at last count, InterShow had amassed a database of 500,000 investors, 150,000 online traders and 50,000 financial advisors, plus a bank of such national celebrity investment experts as Steve Forbes and Harry Dent, who regularly speak at their seminars. They run 11 shows a year in addition to eight specially themed cruises (InterShow is Crystal Cruises' largest group booking agent). In June they launched a brand-new Web site, MoneyShow.com, which they hope will vastly extend their reach and profits. In the investment-seminar business, InterShow simply has no competitors.

None of this came easily. Both Kim and Charles were tossed into the "real" world before they were 18. Charles, who grew up in New Jersey, where his father was an adjunct professor of psychology at Princeton University, moved to Sarasota with his mother after his parents divorced. He was in a car accident that severely fractured his skull when he was 12, and at 14 was sent to school aboard a 154-foot sailboat that traveled around the world. (Called The Flint School and based in Sarasota, it was founded on the principles of objectivism, with a curriculum that stressed laissez-faire capitalism, self-interest and the books of Ayn Rand. Parents could not send money to their children, and the only way students could go ashore with pocket change was to work onboard.) Charles stayed on the ship for two years.

"It was like being in the service," he says, adding that both the accident and The Flint School shaped his life forever. The accident "made me more of a serious young fellow," he says, and The Flint School inculcated him in economics and self-motivation. "It sparked a lifelong love of learning," he says. When Charles was 16, his father died, and Charles was sent to a boarding school in New Jersey.

Kim's father, an Italian immigrant, was 58 when she was born in Miami. He fell ill when she was 15 and could no longer work, so Kim earned her high school degree early and immediately went to work to support him. By the time she was 16, she was already a manager at a Neiman Marcus store in Bal Harbour. (She kept her age a secret from her supervisors.)