The better boss: how Marshall Goldsmith reforms executives.

Marshall Goldsmith is a happy man. He started out happy, he worked on his happiness, and now, at the age of fifty-three, he is very happy. He is, in fact, a happiness professional.

His official job description is "executive coach": he trains executives to behave decently in the office, by subjecting them to a brutal regimen. First, he solicits "360[degree sign] feedback" -- he asks their colleagues and sometimes their families, too, for comprehensive assessments of their strengths and defects -- and he confronts them with what everybody really thinks. Then he makes them apologize and ask for help in getting better. It's a simple method -- "I don't think anybody's going to say I'm guilty of excessive subtlety," he says -- but it works. It had better work. If it doesn't, the client gets his money back.

Goldsmith is so extraordinarily buoyant and extroverted (he scored a perfect E on his Myers-Briggs personality test) that he seems to enter a room in a tinkle of magic dust. If he were shorter (he is nearly six feet), he would look like a leprechaun. His head is round and pink and bald, his eyes are blue, and his chin juts out and upward to meet his nose, like the chin of a wooden puppet. He skips more than walks, and when he is in a bouncy mood (which he usually is) he dances along with his arms straight out and swinging. When he laughs (which he does often), he sounds like a goose. He wears the same outfit every day: green polo shirt, khakis, and moccasins. His favorite movie is "The Wizard of Oz," and his favorite song is "Over the Rainbow." He ends his e-mails and his conversations with what has become his signature phrase: "Life is good!"

The leprechaun quality is one of the reasons Goldsmith is successful. It is a rare executive, after all, who welcomes a man sent by his boss to reform his personality. But people who have worked with Goldsmith call him "disarming," and say that he seems so happy with his life that when he says he is not judging them personally they believe him.

Goldsmith won't take on a client who doesn't want to change -- someone who, as he puts it, has not a skill problem but a don't-give-a-shit problem -- but, short of that, the more obnoxious the better. "My favorite case study was in the 0.1 percentile for treating people with respect," he says. "That means that there were over a thousand people in that company and this person came in dead last. This person would be in an elevator and someone would come up and say, 'Hey, how's it going?,' and he wouldn't even respond. He was hardworking and brilliant; he didn't lie, cheat, or steal. He was just a complete jerk. The case was considered hopeless, but in one year he got up to 53.7 per cent.