Microsoft founder Bill Gates has announced that he will end his day-to-day role in running the software giant within the next two years.
He said that his decision to relinquish all managerial roles by July 2008 would allow him to work full-time for the Bill and Melinda Gates Foundation – a charity funded by the billionaire to help promote health and education projects around the world.
Mr Gates, 50, said that his decision to step down had been a "very hard one", but stressed that he would continue to work "part-time" at Microsoft.
He will continue to serve as chairman of the Washington-based company and act as an adviser on key development projects following the transition.
"Obviously, this decision was a very hard one for me to make," Mr Gates told a news conference last night.
"The change we're seeing today is not a retirement, it's a reordering of my priorities," he insisted.
The world's richest man, estimated to be worth about$50 billion (£27 billion), will be replaced as Microsoft's chief software architect by the company's head technical officer, Ray Ozzie.
Craig Mundie, another chief technical officer, will assume the new title of chief research and strategy officer at Microsoft, Mr Gates added.
Analysts said that news of Mr Gate's decision was unlikely to affect operations at Microsoft given the two-year period he had allowed to make the changes and shares in the company remained largely unaffected by the announcement, climbing just 0.19 per cent to $22.07 on the Nasdaq.
Microsoft, whose Windows operating system runs on an estimated 90 per cent of the world's personal computers, is currently struggling to maintain its dominance in the software market as it attempts to find new sources of growth amid tough competition from internet-based rivals such as Google.