After four decades of military and government service, former secretary of state Colin L. Powell is pursuing a new trail of business entrepreneurship.

Powell said yesterday that he is joining Kleiner Perkins Caufield & Byers, one of Silicon Valley's most storied venture capital firms, to work with young executives on leadership and help their businesses grow worldwide.

Powell, 68, will be a limited partner, remaining in the Washington area but traveling to California or teleconferencing frequently to confer with companies that receive seed funding from the firm. Like other venture capital groups, Kleiner Perkins plays an ongoing role in the management of companies in its stable.

In Kleiner Perkins, the retired four-star general and former chairman of the Joint Chiefs of Staff is joining a 33-year-old Silicon Valley institution that has backed some of the biggest names in technology, including Amazon.com Inc., America Online Inc., Sun Microsystems Inc. and Compaq Computer Corp.

Powell said he was energized by a recent visit to the Mountain View, Calif., headquarters of search giant Google Inc., in which Kleiner Perkins also invested.

"When I walked into the cafeteria area [to give a speech], there were about 1,000 people there," Powell said in an interview. "And I think I increased the average age by about 15 years."

Powell said he also spoke with Google founders Sergey Brin and Larry Page, discussing leadership, organization and "scaling up" a global business.

"People hunger for this," said John Doerr, one of Kleiner Perkins's senior partners. "They hunger for the kind of leadership, wisdom, confidence and inspiration that Colin Powell brings."

Powell has some roots in technology, having served on the board of America Online before its merger with Time Warner Inc. It was in that capacity that he met Doerr, who began pursuing Powell soon after he stepped down as secretary of state.

Powell said he was flattered by an array of new career opportunities but chose Kleiner Perkins for the chance to work with young entrepreneurs.

Powell said he is particularly interested in health care, search, energy and networking ventures. He recently joined a group of executives as investors and board members of Revolution Health Group, billed as a new kind of consumer health care company founded by former America Online chief executive Steve Case.

He added that he wants his work to "have a humanitarian aspect," helping companies bring their technologies to developing countries to help alleviate poverty.

Powell said he bought his first personal computer in 1993, after he left the Army. He said the power of computers was especially evident during Operation Desert Storm in 1991, during which global positioning technology played a prominent role.

Now, Powell said, he has three computers, multiple fax machines and two cell phones in his home office and is "deeply into" online shopping.

Powell said he plans to continue his other business activities. He is active on the lecture circuit and is a partner in one of the groups bidding to purchase the Washington Nationals baseball team.

He has no plans, he said, to run for political office.

Colin L. Powell will be a limited partner in Kleiner Perkins.Colin L. Powell, shown at a June speech, is on the board of a new Steve Case venture and part of a team of investors vying to buy the Nationals.