Herbert D. Kelleher, Southwest Airlines

CEO Herbert D. Kelleher hasn't stopped having fun since 1971, the year he helped start Dallas-based Southwest Airlines Co. (LUV) Neither have his investors, who saw Southwest shares nearly double in price last year, recently hitting $31. In an industry plagued with passenger discontent and labor troubles, the short-hop, low-fare carrier has turned a profit every year for the past 28 years. It also has never laid off anyone and has become an icon of offbeat customer service. Its flight attendants, for example, sometimes sing the flight safety instructions.

Nurturing the "Southwest spirit" may become a little tougher in 2001. Southwest's capacity is expected to grow by 10.5%, in part because it is adding more long-haul flights. Still, the chain-smoking Kelleher, who successfully battled prostate cancer last year ("I don't smoke with my prostate," he jokes) is a shrewd manager who can spot an opportunity anywhere. Since it began operations, Southwest has dropped service in only two cities. It's not a slowing economy or high fuel prices that make him nervous. "What I worry about at night is messing things up ourselves," he says. That's not likely if Kelleher, 69, has a say. After all, it wouldn't be any fun.

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