After taking time off from the business world to become governor of New Jersey, Jon S. Corzine is transitioning back to Wall Street to become the chairman and chief executive officer of MF Global Holdings Ltd.

The 63-year old former chairman and senior partner at Goldman Sachs will join the international brokerage firm effective immediately.

Alison J. Carnwath will be retiring from the board at its next shareholders' meeting in August, after fulfilling her three-year commitment. Bernard W. Dan, the former Chicago Board of Trade chief executive officer, resigned from MF Global [MF] as CEO, a position he held since October 2008, and as a director. He cited personal reasons for his decision, though he will remain with the company through May 16, to help with the transition.

“I see a substantial opportunity for the firm to expand its leadership position in serving clients globally in cash and derivatives markets,” said Corzine, who lost his bid for re-election as New Jersey governor in November. “I look forward to working with MF Global's team to set a strategic path that will take the firm to new levels of growth, profitability and reputation. Profitability and responsibility must go hand in hand with growing our franchise.”

Corzine was governor of New Jersey from 2006 to 2010, and a U.S. Senator from 2001 to 2006. Before entering the Senate, he was chairman and senior partner of Goldman Sachs [GS], where he worked for 24 years, leading Goldman's fixed income division, working to build its presence in Asia and serving as its chief financial officer. He became senior partner of Goldman Sachs in 1994 and became chairman in 1999.

Since last year, MF Global, which was spun off in an IPO three years ago by hedge fund manager Man Financial, has been on a growth spurt, building its high-grade corporate and high-yield business areas as part of its expansion in the fixed income arena, said Niamh Alexander, an equity analyst at Keefe, Bruyette & Woods, who tracks MF Global.

Asia also remains a growth area where the brokerage company has added sales and trading professionals, Alexander said. MF Global has also stepped up its presence in the government agency debt business.

There have been notable changes within management as well. In April 2008, Randy MacDonald, who filled several roles at TD Ameritrade Holding from 2000 to 2007, was hired as chief financial officer. Robert Lyons joined in September as chief operating officer for North America after spending more than 20 years at Bear Stearns. And in October, James O'Sullivan was hired as MF Global's chief economist, coming from a similar role at UBS.

Yet there has been trouble at the brokerage firm. In December, Commodity Futures Trading Commission regulators fined MF Global $10 million for risk-management practices related to a rogue futures trader's actions in 2008.

MF Global expects to release earnings in mid-May and projects its net revenues for its fiscal fourth quarter, which ends March 31, will be in the range of $235 million to $245 million. The company believes its capital and liquidity position won’t significantly change from the previous quarter.