Little-Known Fund Manager Oversees $800 Billion

Unlike other firms, Vanguard doesn’t separate the jobs of portfolio manager and trader. A portfolio manager must know not just what to buy and sell but where to do so. “They have a much tougher job than they used to,” Bruce says, given the increased complexity of the stock market. There are a dozen stock exchanges and more than 40 pools of liquidity in which trades can be executed.O’Reilly’s friends and family back in Ireland don’t really understand what he does. Even on Vanguard’s campus, 28 miles outside Philadelphia, he barely attracts attention. He can visit the Galley—the cafeteria whose name, like everything else on the campus, reflects the firm’s nautical theme—without being recognized as the manager of Vanguard’s largest fund.

“That’s a good thing,” O’Reilly says. Even though his name is on the fund paperwork, he says, managing an index fund is a team effort. “There’s a great camaraderie on the desk,” he says.

“If you have any kind of an ego, it’s going to get cut down pretty quickly,” he says. “If I come in with a bad haircut, I’m going to hear about it.”Steverman covers personal finance at Bloomberg News in New York.