(Fortune Magazine) -- The Al Manzil Hotel in Dubai has been open for business all of 18 days on the Saturday night in January that I show up with Ram Charan. The lobby is strangely quiet; there doesn't seem to be anybody else staying here. The surrounding neighborhood is called Old Town, but in fact it's a construction site from which are rising what will one day be the world's tallest skyscraper and the world's biggest mall. Soulless and kind of creepy, I'm thinking, but Charan's thoughts are elsewhere.

Already he has claimed an overstuffed chair in the center of the lobby and is talking on the phone. After 12 hours of isolation on the flight from J.F.K., Charan is back in business, deep in private conversation with a client in New York City. He looks tired, and no wonder. He began his day with a 4 A.M. Friday wake-up call in Richmond (he did a Squawk Box live remote on CNBC), and he has a head cold. But he is in no hurry to go to bed. Charan doesn't care what time it is. He doesn't care what day of the week it is. And the last thing he cares about is where he is. As long as Charan is with a client - or can get one on the phone - he's home.

Thirty years ago this month, Ram Charan (pronounced "Rahm Scha-RON") quit a tenured professorship at Boston University to devote himself full-time to consulting. Today he's alone at the top of his profession - not a consultant so much as a guru, a corporate sage, with unparalleled access to boardrooms across the globe and intimate, enduring relationships with an array of powerful CEOs.

Among them: Jack Welch, formerly of GE (Charts, Fortune 500), who says of Charan, "He has this rare ability to distill meaningful from meaningless and transfer it to others in a quiet, effective way without destroying confidences"; Dick Harrington of Thomson Corp. (Charts) ("He probably knows more about corporate America than anybody"); and Verizon's (Charts, Fortune 500) Ivan Seidenberg ("I love him. He's my secret weapon"). "He's like your conscience," says former Citicorp CEO John Reed. "Just when you sort of think you have everything done and you're feeling pretty good about yourself, he calls you up and says, 'Hey, Reed, did you do this and that and the other?'"

There's another aspect of Charan, not unrelated to his success, that sets him apart from his peers, if not the whole human race: what Jack Krol calls Charan's "strange existence." "When I was chairman and CEO of DuPont," says Krol, "he'd show up at the house Sunday morning at nine, and we might spend three or four hours, and all of a sudden he'd disappear. He would go anywhere at any time that you asked him to meet with you. Business is his whole life."

That sounds like an exaggeration, but it's not. Having uploaded himself into the global economy, Charan circulates, continuously, with something like the speed and efficiency of capital. Consider the itinerary he sketched at dinner one night a few months ago in New York. He had just agreed - for the first time in his career -to let a journalist travel with him and watch him work. "I should tell you where I've been the last few weeks," he began in heavily accented English. "I go to India on the Friday of the week before Thanksgiving. I am Sunday morning in Bombay. Monday morning I am in Delhi. Wednesday I'm in Bombay. Thursday I'm in Bangalore. Saturday I'm in Trivandrum. Wednesday I'm in Johannesburg. Friday morning, at seven, I am in New York. I have a two-hour meeting with a CEO who has flown in to see me. I have two more meetings and I fly out that night to Dubai. I am in Dubai on Sunday and Monday, then I come back here. On Thursday night I fly out to Jubail, Saudi Arabia. Then I come back here. Tuesday morning I have a whole-day schedule in New York. Tuesday night I go to Milwaukee. I came from Milwaukee last night. They diverted my plane so I had to stay in Pittsburgh. I had a meeting this morning in Philadelphia. I had three meetings here in the afternoon. And I'm here tomorrow, with GE. Then an hour-and-a-half phone call. Then I'm going out tomorrow night to West Palm Beach. Monday morning I have a breakfast meeting in New York. And then I'm flying out to Perth, Australia." At least he flies first-class.

Now consider what comes next: more of the same. Charan never stops. He sleeps in a hotel every night ("Professor Charan, welcome home," is how the doorman greets him at the Waldorf on Park Avenue), except when he's sleeping on a plane or, rarely, in someone's house, which can happen when a client takes pity on him. "I got in the habit of having him over for Christmas because he had no place to go," says Reed. "He was going to sit in a hotel room. That's hardly right."

Before he was a consultant, Charan lived in dormitories. Before he was a professor and a student, he lived in YMCAs. Now he doesn't live anywhere. Charan's one nod to a conventional rooted life is the office he rents on North Central Expressway in Dallas (that's the address on his passport - he is a U.S. citizen), but he can't tell you anything about it because he's never been there.

"I really thought the two ladies I interviewed with six years ago were just yanking my chain," says Cynthia Burr, who manages Charan's hideous schedule. "I said, 'Where does he keep his stuff? Everybody has stuff.' It's really hard to wrap your arms around something like that, but it's true."

Three days a week - on Monday, Wednesday, and Friday - Burr and a colleague pack a cardboard box with shirts, underwear, and socks, perhaps a clean suit (there is a tailor at Neiman Marcus who has Charan's measurements on file), and maybe a V-neck sweater or a pair of khaki pants. They toss in toothpaste, razors, shampoo, a shined pair of 9� EEEE shoes, whatever he needs ("He doesn't buy anything himself," says Burr), and send it by FedEx to Charan's hotel, wherever that may be. The box comes back two days later filled with dirty laundry.

Charan doesn't own a car because he never learned how to drive, and besides, where would he keep it? A plane, perhaps? With a day rate that clients say can top $20,000, he could afford one. "If I was Ram, the one thing I'd have is one hell of a nice plane," says his friend Bill Conaty, senior VP for human resources at GE. But Charan is not Conaty. "I use the time sitting in the terminal," he says. "I have never missed an appointment in my life. I don't want to get lost in this private-plane business." (He does regret, however, not accepting an offer from American Airlines in the 1970s to buy a lifetime first-class upgrade for $100,000.)

He trundles through airports pulling a mismatched pair of black canvas rollers, one held together with maroon duct tape. His watch is a Timex. Given all the hours he spends in transit and his lifelong passion for the Indian vocalist Lata Mangeshkar, I suggested once that he might enjoy an iPod. The idea seemed to upset him: "No, I don't do that, I couldn't do it. Would just distract me. Music can make you very sentimental. Couldn't do it."

Have I mentioned that Charan has never married? That he has no children? And still I haven't come to possibly the most peculiar aspect of his personality. I mean that which sets him apart from virtually every person he comes in contact with, none more so than his overachieving CEO clients: Charan has no goals. He never set out to become a globetrotting consultant, any more than he dreamed of attending Harvard Business School, or becoming a professor, or even so much as one day earning a living beyond the small city in India where he was born.