The board of Prudential Financial Inc. has picked John Strangfeld, a vice chairman, to take over as chief executive officer and as chairman.

Arthur Ryan, 65, the current chairman and CEO of Prudential, will step down as CEO Jan. 1, 2008, and as chairman in May 2008, according to Prudential, Newark, N.J.

Strangfeld, 53, has been running Prudential’s investment management and U.S. life and annuities operations.

Mark Grier, 55, the Prudential vice chairman who has been running the company’s international operations, will join the Prudential board and an “Office of the Chairman,” Prudential says.

Ryan has been running Prudential since 1994. The decision to make Strangfeld Ryan’s successor is the result of a succession planning process that started about 2 years ago, Prudential says.

Strangfeld has a bachelor’s degree in business from Susquehanna University and a master’s degree in business from the University of Virginia. He holds the Chartered Financial Analyst professional designation, and he is president of the board of the Darden School Foundation, a group that supports the University of Virginia’s Darden School of Business.

Grier began working for Prudential as chief financial officer in 1995. He became vice chairman in 2002. He has a bachelor’s degree and a master’s degree in economics from Eastern Illinois University along with a master’s degree in business from the University of Rochester.