The 106-foot yacht that Sarasota's Norm and Susan Worthington bought last October in Fort Lauderdale for their young family came with a fancy name, Grand Cru, and glitzy interiors as well. But the Worthingtons wanted something more than a luxurious vessel for occasional showy cruises. They have a grand plan for the Grand Cru, one that required a new look for the yacht.

The couple met in Sarasota as New College students and returned here to bring up their children after Norm founded and ran several successful high-tech companies in California. In Sarasota, Worthington has indulged his love of boats; he currently owns 10, from an inflatable dinghy to a 35-foot sport fishing boat up to the new yacht. "The family teases me by calling me the admiral," he admits. "I'm crazy about boats, and I'm a fanatic fisherman. And our family loves to travel by boat." And that led to their grand plan, he says: " In about a year Susan and I will take our son and daughter out of school for a year and we'll travel around the world."

Such a lengthy voyage will require a comfortable, family-friendly environment, so the Worthingtons asked interior designer Jonathan Slentz to give the yacht a makeover. "The original decor was over-the-top Miami, with silk on the walls, damask upholstered furniture and very high-style accessories," says Slentz. "We left the gold leaf ceilings because they're really beautiful and bring a lot of light into the spaces, but changed just about everything else to make the boat a relaxing haven for Norm, Susan and their daughter and son."

Slentz knows the family's style; he did their Siesta Key home about eight years ago in a relaxed tropical motif. For the boat, they wanted "whimsical island" with blues and greens for the public, high- traffic areas of the boat and touches of yellow and violet in the bedrooms. The sitting room is violet, yellow and shades of orange. "No florals anywhere," stresses the designer. "And the fabrics, such as denim, stain-resistant cotton and new microfibers, were selected for durability for casual entertaining and long family trips. We used a pineapple motif on the dining room chairs and plenty of checks, plaids and blocks of solid color to make a lively but not busy decor scheme."

Damask wallcoverings were replaced with vinyl. The designer left the built-ins, recovering some surfaces and refreshing the beautiful, light-colored wood on the fireplace, bar, wine racks and various storage units. The wood, called sem , is different hardwoods pieced together to create an exotic veneer; and it, along with the quality of craftsmanship, were helped sell Worthington on the floating vacation home. The galley was already shipshape and just needed cosmetic upgrades and a few new appliances. There are three freezers and two refrigerators on board. "When we're out, we don't want to cook," explains Worthington. "So a local private chef prepares meals for us in advance and freezes them. The stewardess defrosts and serves them. We keep things pretty simple." The boat requires a crew of three, including a captain.

The family has been making short trips to get ready for their big adventure, and Worthington says they realized they needed a big boat because they'd be on it for long periods of time. "We all want comfort, privacy and space to do our own things," he explains. "Susan, for instance, is a painter, and she'll bring her supplies on board. We also needed a big boat for practical reasons. The Grand Cru can go 3,000 miles on one fill-up. It has a 9,000-gallon tank. When you're planning to go around the world, that's critical."

Worthington is also considering making the Grand Cru a luxurious floating fishing lodge in an enterprise he calls Big Gulf Adventure. Worthington explains: "About 115 miles west of Sarasota is a big game Gulf fishing area called The Steps because of the drop-off. It's a place where two currents operate, so the spot is potentially dangerous. But it's incredible-you can see half a dozen marlin at one time-and sport fishermen love the challenge of the place." He plans to anchor the Grand Cru nearby, so fishermen can take their 35-foot boats out to The Steps, fish all day and come back to the big boat for dinner, a shower and relaxation. The next morning they can go out again. "I've fished The Steps and I know that a fishing lodge right on the water nearby would have great appeal," he says. He hopes to offer this innovative charter experience "in the near future," he says.

The Grand Cru was commissioned in the late '80s, and the Worthingtons are its fifth owners. "In many ways a boat is a lot more difficult to update and renovate than a house," says Slentz. "Nothing is exactly square or level or standard size. And nearly everything is built-in or in some way permanently attached for safety and efficiency. Artwork is nailed to the wall, and you need non-corrosive metal light fixtures. Everything has a purpose, and you cannot compromise that purpose. The designer's job is to enhance function by providing comfort and good looks."

This is the sixth boat that Slentz has done in the past eight years, and all of them belong to clients whose homes he did first. "I look at a boat as a guest cottage or a vacation home that just happens to float," says the designer. "And I never do a nautical theme. That would be just too much of a cliché."