The world’s richest man doesn’t often find his way to Capitol Hill. And when he does, he tends to be discreet about it. Last week was no exception.

Officially, Microsoft Corp. Chairman Bill Gates came to Washington for a panel discussion at the Library of Congress. But while he was on the Hill, he also dropped by for a couple of closed-door meetings with lawmakers.

One was with the Congressional delegation from Washington state, where his company is headquartered. The other, about an hour in length, was with Members and staffers of the Senate Commerce, Science and Transportation Committee, to discuss challenges facing the technology industry.

“It was an informal opportunity to engage in a free-flowing discussion,” said a source familiar with the meeting.

The source added that Gates talked about “big-picture, vision stuff” instead of lobbying for specific pieces of legislation. “He was talking about where technology is going — how it is going to impact priorities in terms of public sector leadership.”

Committee staffers and company officials were mostly mum about the skull session because it was part of a series of “listening sessions” arranged by Chairman Ted Stevens (R-Alaska) as committee members prepare to rewrite several bills including the landmark 1996 Telecommunications Act.

“They’re closed-door, off-the-record meetings,” committee spokesman Aaron Saunders said. “Because they’re closed-door, we don’t discuss them. That’s the agreement with the Members and the folks appearing before the committee.”

In his appearance, the source said, Gates did the talking, answering questions from Senators.

He discussed the “vitality” of the universal service fund — the telecom industry-funded pool that is used to subsidize service in rural areas. Experts fear it could dry up if its funding formula isn’t changed, but Gates had no easy answers for the Senators, acknowledging that the problem is a “significant challenge,” the source said.

Gates also talked about Voice Over Internet Protocol, the so-far unregulated service that allows users to make phone calls using Internet connections.

Though neither issue stands to significantly impact Microsoft’s bottom line, both could come up when the committee tackles telecom legislation this year.

Picking up on an argument he made during the panel discussion Wednesday, Gates told the Senators and staffers about the need to make sure American technology companies have access to an American work force that’s well-educated.

The visit to the Hill was the first in two years for the Microsoft chairman. The last time Gates was in town, he gave a speech at the Center for Strategic and International Studies, said Ginny Terzano, Microsoft’s Washington spokeswoman.

Though Gates is an infrequent visitor, Terzano said he is “quite knowledgeable and very attuned” to activity in Washington that affects his company.

She said Gates is only one of many Microsoft executives to beat a path from the company’s Redmond, Wash., headquarters to Washington periodically. And while Gates didn’t buttonhole Members about specific legislation in his meeting last week, Terzano said company officials make their trips to “engage in a conversation that’s going to be most impactful in moving forward a technology agenda that’s going to be positive for the industry.”

The company famously learned its lesson about the importance of Washington in the 1990s, after the Justice Department slapped the company, then averse to lobbying, with a massive antitrust suit. A decade ago, Microsoft did not even have a Washington office — ironic, perhaps, given that Gates’ father, Bill Gates Sr., was a co-founder of the law firm Preston Gates Ellis & Rouvelas Meeds, which has since become a major presence on K Street.

Since then, the company has ramped up its staff and its outlays, spending $8.7 million on inside and outside lobbying in 2003 alone, according to PoliticalMoneyLine.

Now, with the federal antitrust suit settled, Gates is free to focus his conversations with Members on public policy and how it affects the technology industry.

Indeed, competition and antitrust issues “didn’t come up once” during the Thursday meeting, said the source close to the meeting.

“Many legislators wanted to get beyond the DOJ aspect,” Terzano said. “They are more concerned with the core issues.”