John J. Mack

Age: 64

WHAT HE DOES
John Mack steers one of the world’s largest investment banks, with $693 billion under management and more than 55,000 employees, toward ever greater returns.

WHAT HE’S KNOWN FOR
Mack got into an executive smackdown with Phil Purcell, who became C.E.O. of Morgan Stanley following its $10 billion merger with Dean Witter in 1997. Mack, who orchestrated the merger as president of Morgan Stanley, had a handshake agreement with Purcell to succeed him in five years. When Purcell refused to budge, Mack bailed. But in 2005, Purcell was forced out after several high-profile executive departures, and “Mack the Knife” returned to take his place. Mack’s revenge was made even sweeter by the $40 million in compensation he took home the next year.

WHERE HE’S FROM
The son of Lebanese parents, Mack was born John Machoul. But his father, who worked as a small-time retailer in North Carolina, changed the family name. Mack attended Duke (where he is now a trustee) on a football scholarship. He studied history and ran an after-hours snack joint from his dorm room before graduating in 1968.

Mack joined Morgan Stanley as a bond trader in 1972, became a vice president just four years later, and was elevated to managing director in 1979. In that position, Mack made Morgan’s taxable fixed-income division one of the most profitable on Wall Street, and in 1993, he had become the company’s president.

During his slog to the top, Mack earned his nickname for both his managerial efficiency and his ruthless manner with subordinates. “There’s blood in the water, let’s go kill,” was a favorite rallying cry, according to Wall Street lore, and Mack became notorious for holding screaming matches on the trading floor and focusing obsessively on department consolidation and cost cutting.

In 2001, Mack left Morgan Stanley to become C.E.O. of Credit Suisse First Boston, where he was tasked with staunching out-of-control spending. Mack boldly slashed salaries by appealing directly to bankers: In a series of one-on-one conversations, he bullied, charmed, and persuaded money-hungry Wall Streeters to take compensation cuts for the good of the firm. He flew halfway across the country to meet Frank Quattrone, a company star, only to open the negotiation by threatening to tear up Quattrone’s contract. Yet Quattrone agreed to new terms once Mack offered him a spot on C.S.F.B.’s board. In another instance, Mack had Duke basketball coach Mike Krzyzewski call an employee, an avid fan, to thank him on Mack’s behalf for persuading his department to return $50 million in compensation to the firm as part of cost-cutting measures.

In three years, Mack eliminated 10,000 jobs, reduced costs by $3 billion, and presided as bankers returned more than $400 million in guaranteed compensation. Turning C.S.F.B. into a profitable concern was a task that, he later said, got “my blood pumping.”

WHERE HE’S GOING
Ensconced once again within Morgan Stanley, Mack has a lot to look forward to—more banner years of compensation, for one thing. A demanding leader and political infighter throughout his career, Mack has mellowed ever so slightly in recent years. In a 2003 address to Harvard Business School students, he said his management style had gotten “softer,” and he emphasized the importance of teamwork and a “one firm” mentality—not putting one’s own pay ahead of the well-being of the company.

But Mack still has things to attack. Despite all the feel-good energy at the firm, shareholders are concerned that Morgan Stanley’s stock performance lags behind that of its competitors—in particular, archnemesis Goldman Sachs. —Sophia Banay