There is nothing harder to teach anyone than how to provide good service," says David Klein, who has spent seven years training the limousine drivers who work for his $10-million company, Dav-El Services Inc., in New York City, Los Angeles, and Washington, D.C.

After years of reviewing the basics of courtesy ("don't leave french fries on the front seat"), and respect for privacy ("don't ask rock stars for their autographs"), he grew bored. "I couldn't teach anymore. I felt like I was going to bust," says the 39-year-old Klein.

He relieved his frustration by transferring his litany of manners into six easy-to-digest, prerecorded programs. "With video you can show so much," Klein says. Rather than hearing him drone on about keeping their breath sweet, trainees watch a driver on tape munching on a bulb of garlic while the executive in the backseat holds his nose. The tapes are augmented by lectures on driving technique and behind-the-wheel training.

An outside video-production company produced the whole training package for $15,000. Klein and Lou Brooks, a full-time training instructor, collaborated on writing the material and cast Dav-El chauffeurs and administrative personnel as the actors. Klein has even managed to turn a profit on the venture by selling the package to other limousine services for $1,000 apiece.

As Lou Brooks puts it: "In this business, everything is attitude and presentation. We teach them the beauty of class."