Motorola chief executive Ed Zander is to step down and will be replaced by company president and chief operating officer Greg Brown, from 1 January, 2008.
The company said Zander will continue to serve as chairman of the board of directors until the annual meeting of shareholders in May 2008.
Samuel C Scott III, lead director of Motorola's board of directors, said in a statement: "I want to take this opportunity to thank Ed for his vision, expertise and tireless commitment to Motorola. We greatly appreciate his many contributions and wish him all the best in the years ahead. Today's decision is the culmination of a thoughtful and disciplined process of succession planning."
Motorola has been having a tough time of late, and has failed to return to the kind of form it enjoyed back in 2005 when its Razr phone took the market by storm. There was even talk in some quarters of the company overtaking Nokia as number-one handset maker in the world. But there has been no new Razr success story and Motorola has slipped to number three in the handset rankings.
Carolina Milanesi, research director at analyst Garner, said Zander's resignation is not surprising. "We were expecting it," she said. "Everybody's been waiting for Ed to move aside and let room for someone else to try and get Motorola to wherever it's supposed to be.
"On the devices side they lost the number-two position worldwide. Market share has been going down every quarter. They really are a pale version of the company they were a year ago."
A Motorola spokesman said Zander had "decided to retire", adding: "The board and Ed Zander agreed it was the right time for him to transition the role of chief executive to Greg Brown and Ed remains committed to Motorola and assisting Greg and the company through the transition." Brown has served as Motorola's president and chief operating officer since March 2007 and has headed up four different businesses during his time with the company which he joined back in 2003. He also led the $3.9bn (£2bn) acquisition of Symbol Technologies, bolstering Motorola's enterprise offerings.
Gartner's Milanesi said Brown is "somebody that was already seen as somebody who could turn things around as he was given the leadership of the devices business", adding: "And given how much the devices part makes up of the overall Motorola business I think it makes sense that he's entrusted with this position."
But she warned: "He's got a tough job on his hands."
Milanesi doesn't see a big shake-up being needed at Motorola but said a lot of attention needs to be paid to the day-to-day detail. "As far as the devices business is concerned it's really a question of sorting out the portfolio, rationalising their software and platform strategy, having a better cost structure, focusing on distribution in some of the key emerging markets," she said. "There's lots of different things that need to be sorted out on a daily basis."
Motorola's spokesman added: "Greg will be communicating with employees in an on-going way starting in January about what he intends to do as we move forward."