Who will succeed Steve Ballmer at Microsoft?

Whoever succeeds Steve Ballmer as Microsoft's chief executive will have to make up for a lot of lost time. The reason? Microsoft (MSFT), once the dominant technology company, is fighting obsolescence. It failed to capitalize on the biggest technology trends of the past decade -- mobile devices and Internet search -- and must now play catch-up to rivals like Google (GOOG) and Apple (AAPL). Microsoft disclosed its search for a new leader on Friday. Ballmer, the voluble salesman who has led the company since 2000, said he planned to resign within the next 12 months. There are a number of potential successors, but no obvious front-runner has emerged. Whoever is chosen must be comfortable in the spotlight along with the intense pressure that comes with trying to revive such a high-profile company. Candidates must be well versed in technology and have experience at a large public company. Familiarity with Microsoft's business, which still depends heavily on selling Windows desktop software, is a plus. Microsoft's board will likely consider a number of internal candidates. But there are also executives from an array of other companies like Facebook (FB), Nokia (NOK), and Juniper Networks (JNPR) who could step into the role. Whether the board gives the job to an insider or outsider could be telling. Boards seeking modest reorganizations and smooth transitions typically choose an internal candidate. Picking an outsider usually signals a more radical approach. What follows are some of the potential candidates for Microsoft's chief executive job, their selling points and their liabilities.

Sheryl Sandberg

Facebook's meteoric success can be largely traced back to Sandberg. She brought the management experience that Mark Zuckerberg, the company's twentysomething founder, lacked. They work as a team. But at some point, she may want to lead a company on her own. Sandberg would bring considerable buzz to Microsoft. The question is whether her skills in the Internet realm are applicable to selling software, servers, and video game consoles.

Kevin Johnson

Johnson is among a legion of former Microsoft executives who have gone to lead other companies. He joined Juniper Networks, the computer networking gear maker, five years ago. Last month, he disclosed plans to resign as soon as a replacement is found. Johnson's keen familiarity with Microsoft -- he once presided over its Windows and online services division -- is a definite plus. Whether he can breathe innovation into the company, something it sorely lacks, is an open question.

Tony Bates

Bates, a native of England, has a proven track record as both a technologist and business leader controlling a multibillion dollar budget. Currently, he leads Microsoft's business development, strategy, and evangelism -- which involves the important job of keeping the company's many partners happy. Prior, he served as chief executive of Skype, the online calling service, and as a top executive at Cisco Systems (CSCO). His experience with both consumer and enterprise products would be an attractive combination.

Ed Breen

Tyco, a maker of security systems and fire protection equipment, isn't exactly a household name in the technology world. But Breen, who resigned from Tyco (TYC) earlier this year after more than a decade as chief executive, would bring loads of experience in one important area: corporate reorganization. He revamped Tyco, a one-time conglomerate, by installing a new board, selling off business units, and shifting what remained into separate companies.

Kevin Turner

Microsoft's board will almost certainly give serious consideration to Turner, the de facto No. 2, as Ballmer's successor. Much of the nuts and bolts of the company -- sales and support, for example -- are under his purview. Of anyone, Turner may know Microsoft's business and operations the best. But he may also be seen as too associated with the current problems at the company and lacking the vision and technical chops of some other potential candidates.

Stephen Elop

Elop, who has held executive positions as Microsoft, Juniper Networks, and Adobe (ADBE), is an obvious candidate to succeed Ballmer based on his resume. He knows the technology industry and Microsoft in particular, having led the all-important group that makes Office. Most recently, he's been trying to turn around Nokia, the troubled mobile phone maker. However, his strategy of adopting the Windows operating system for Nokia's smartphones hasn't exactly been a hit with customers, and it will likely count against him.

Qi Lu

Personality-wise, Lu, who oversees Microsoft's Office software and online Bing search engine, is a polar opposite of Ballmer. Lu is sedate while Ballmer is volatile. Lu's engineering mentality and focus on innovation may be a welcome change. But the board may be looking for someone with more extensive experience leading a company.

Satya Nadella

If loyalty counts, Nadella is a front-runner. He joined Microsoft more than 20 years ago and currently is head of the company's cloud computing, data center, and enterprise division. It's a highly profitable but largely invisible area that Microsoft is counting on for future growth. Combine that with the fact that he's well-known inside the company, and he may be a serious contender.