Tom Whidden is one of those lucky and rare fellows who has successfully carved a career out of a passion.

At the tender age of 18, Mr. Whidden decided that he wanted to be a sail maker, an activity that, like candle making or book binding, involves Old World artisanship and not much cash. Fortunately for Mr. Whidden, his company developed a technology that advanced the state of the art, and in due course Mr. Whidden and his partners became the world’s foremost suppliers of sails. In the most recent America’s Cup competition, every boat but one carried his company’s sails; the Chinese used their own design and came in dead last.

Mr. Whidden today runs and is part owner of a diversified outfit called North Marine Group, which boasts revenues of about $250 million, most of them from nautical businesses. The firm has several divisions, including EdgeWater, a manufacturer of outboard powerboats and North Sails Sportswear, which last year sold more than one million pieces of nautical-themed clothing. However, the firm’s principal activity, and certainly the core of its reputation, remains the manufacturing of sails.

North Sails makes the most expensive sails in the world — an America’s Cup mainsail can cost up to $70,000, which admittedly is a rounding error in the $100 million budget of some teams — as well as the sails sold with the small Sunfishes and Sailfishes that populate family resorts. It is in the high end that the company has firmly gained technological leadership.

“We’ve owned the sophisticated sail market for a long time,” Mr. Whidden says. “We have about 80% market share.”

Winning the America’s Cup competition will have that kind of impact in the technology-hungry racing world. In 1992, the first boat to adopt the company’s 3DL sail technology came in first. Though Mr. Whidden modestly says, “It would be a stretch to say it caused the success,” evidently the racing world thought otherwise. The next time around, in 1995, every boat but one was flying the new sails.

The breakthrough came from a group in landlocked Switzerland, of all places, where competing on Lake Geneva is the proving ground for the country’s avid sailors.

“People had been making sails the same way for 4,000 years — taking fabric and cutting and sewing it to size. Our sails are made all in one piece, on a mold. They have film on the outside and carbon fiber on the inside,” Mr. Whidden explains.

The advantage of the new molded design was that sails could be one-third lighter and considerably tougher. Consequently, a boat could hoist more sail while not adding weight, a combination that boosts speed. Another plus is that the old-fashioned manufacturing approach required a three-month lag between conception and creation. Today, a team faced with a change in weather or strategy can order up a new sail and receive delivery in just a few days. Mr. Whidden has not viewed these developments from his desk. He has competed in eight America’s Cup tournaments and sailed in the finals five times. He has raced many times with the legendary skipper of Stars & Stripes, Dennis Conner, and has often served as boat tactician. In this role he has offered strategic advice and acted as a liaison between the crew and the captain, a job that requires know-how and considerable diplomacy.

Mr. Whidden grew up seaside in Westport, Conn., and jumped into racing at 18, sailing a boat called a Finn. After graduating from Colby College, he joined AMF, which had recently bought a manufacturer of sports boats, Alcort Boats. After a fortuitous brush with then-CEO Rodney Gott, Mr. Whidden was thrust into AMF’s management training program, whereby he picked up some handy financial skills.

Two years later, however, he left the company to try out for a spot on the Olympic sailing team. He made it to the finals, but more importantly, trained with a fellow who was a sail maker and who became his partner for the next 15 years. Together they bought a company called a successful manufacturer of sails, Sobstad.

In 1987, the two parted company when Mr. Whidden went off to Australia to join Mr. Conner’s quest to bring the America’s Cup home. Shortly thereafter, Mr. Whidden joined North Sails.

This year, Mr. Whidden turns 60, and enjoys sailing at a more leisurely pace. “I sail maybe 50 or 60 days a year and I meet the most amazing people,” he says. In the next few weeks, he’s heading for a regatta in France and also looking forward to an outing in Sardinia. He sails on boats owned by customers like the kings of Spain and Norway, and moguls like Larry Ellison of Oracle.

He has seen the sport become popular all over the world. “Sailing is faddish, especially in Europe,” he says. “In Italy, all the fashion people like Loro Piana and Ferragamo have taken up sailing. In the U.S., I think the numbers of sailors is flat. It used to be that our business was half in the U.S. and half in Europe. Now it’s about 75% Europe.”

Mr. Whidden does his bit to promote the sport in America. Just recently he was in Nantucket presiding over an auction raising money for a local community sailing program. “Kids brought up sailing are terrific kids,” he says. “Sailing has been great to me; I definitely want to give something back.”

What’s next? Mr. Whidden appears to be having too much fun to consider retirement: “I don’t think I’d like not working.” On the other hand, he has to be on guard that his company stays at the forefront of new technology.

To that end, he has just invested $15 million in a new technique that could prove the next big thing in sail making.

“Sailboat racing is about making the fewest number of mistakes,” Mr. Whidden says. As in life, and in business.