Gates Plans to Make Philanthropy His Top Focus Starting in 2008

Bill Gates, the world's wealthiest man, announced on Thursday that he will end his day-to-day oversight of

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the Microsoft Corporation to devote more time to the foundation that bears his name, a decision that some observers say reflects his ambition to become one of history's greatest philanthropists.

Mr. Gates, 50, said he will continue to serve as the Seattle software company's chairman but by July 2008 he will cease his daily responsibilities at Microsoft to focus on the Bill & Melinda Gates Foundation. Mr. Gates chairs the philanthropy along with his wife, Melinda, and his father.

"This was a hard decision for me," Mr. Gates said in a statement. "I'm very lucky to have two passions that I feel are so important and so challenging."

The foundation said that Mrs. Gates, a former Microsoft executive herself, will also be devoting more time to philanthropy.

"The foundation's staff and leadership benefit greatly from Bill and Melinda's continued and growing involvement in our work," Patty Stonesifer, the fund's chief executive, said in a statement. "Together, they set the strategic direction and provide deep and thoughtful counsel on what we're learning, how we're developing and implementing solutions, and how we're measuring results."

The Gates Foundation, in Seattle, is the largest charitable fund in the United States, with $29.1-billion in assets. The grant maker focuses on global health, U.S. education, public libraries, and social services in the Pacific Northwest.

In April, the foundation said it would be expanding the number of causes it supports by providing more money to agricultural projects and to efforts that expand financial services for the poor in Africa and other impoverished regions of the world. The foundation appointed a new manager to lead this effort, as well as new people to lead its global health programs and to oversee its giving in the United States.

In addition to the personnel changes, the foundation is also building a new headquarters in downtown Seattle to house its growing operations.

Ms. Stonesifer said on Thursday that Mr. Gates's decision will not lead to additional changes in programs or leadership at the foundation. "No other organizational changes are planned," she said.

Staff members who oversee grant-making programs at the foundation have said Mr. Gates has been involved in its work since the fund's inception six years ago, often asking detailed questions about complex issues. For example, Mr. Gates has shown an unwavering intellectual curiosity for even the lesser-known diseases the foundation fights, such as hookworm.

But while Mr. Gates was involved in the philanthropy, foundation officials have said he worked mostly on foundation tasks on the weekends, often sending e-mails to them from home, and rarely occupied the office he had in the foundation's current headquarters building.

Mr. Gates has said that eventually he would like to donate up to 90 percent of his wealth, currently estimated by Forbes magazine at about $50-billion.

In an e-mail correspondence with The Chronicle in 2004, Mrs. Gates said she and her husband had yet to decide if they want their foundation to exist indefinitely. If, say, scientists discovered a vaccine for HIV/AIDS, she said, the couple would be keen on spending all of the fund's assets to make sure the potential drug reached the poorest parts of the globe.