About a thousand people joined Bill and Melinda Gates Thursday night to celebrate the opening of the foundation's new campus in Seattle.

"You know when you work on a project like this you start with a goal," Melinda Gates said. "And at the end of the day, this campus is about us having an impact on the world for the people we serve, whether they are in Bangladesh or in Boston or in Botswana or Nigeria."

The foundation spends most of its money on global health, with sizable sums going to global development and efforts to improve public schools in the U.S.

In order to keep its tax-exempt status, the foundation has to give away about $3 billion a year. Stacy Palmer, editor of the Chronicle of Philanthropy, says the foundation's influence goes far beyond that.

Taking Over?

"They're influencing governments in lots of different ways — and corporations, and really everybody else in society, and it's not just about writing checks," she says.

It's about setting agendas, framing debates, advocating the foundation's point of view and taking action. Palmer says the foundation has changed the perception of what a private organization can do.

"And that is a good thing," she says. "Because it's getting more people involved. But if you don't like what their agenda is — then it's an unchecked way of getting things done and that bothers a lot of people."

Right now, for example, there's a lot of talk about the foundation's effort to improve public schools. It's focusing on better classroom instruction and is using data — including student test scores — to gauge how well teachers are doing.

"I have no doubt that the movement Bill Gates has launched has created enormous hostility toward teachers," says Diane Ravitch, who has been studying American education for 40 years.

The New York University professor has emerged as the most outspoken critic of the foundation's approach.

"It's like all accountability for educational failure is suddenly plopped on the heads of teachers, and this is wrong," she says.

Moreover, Ravitch contends that when the foundation supports think tanks, academics and others who agree with its point of view, it drowns out other voices. Referring to Bill Gates, she says, one man shouldn't have so much power.

Achieving Objectives

"I think Diane is really underestimating the number of voices that are out there, including her own," says Jeff Raikes, CEO of the Gates Foundation.

He dismisses Ravitch's contention that the foundation has commandeered the education debate. At the same time he makes no apologies for the organization's doggedness in trying to achieve its objectives.

"We do think a very important part of our role is to really shine a spotlight on the key issues that lead to inequity in the world," he says.

EnlargeAftab Alam Siddiqui/AP

Microsoft Corp. founder and philanthropist Bill Gates and his wife Melinda Gates attend to a child as they meet with members of the Mushar community at Jamsot Village near Patna, India, on March 23.

"And I always like to say that even if our grants don't always succeed, the only failure is if we don't learn because part of what we have to do in order to contribute to society is, we have to take risks," Raikes says.

Like most foundations, the Gates organization works with partners and grantees — thousands of them — who do the heavy lifting on the ground. And having strong relationships with them is critical.

But in an independent survey last year, many partners said the foundation didn't understand their goals, was inconsistent in its communications and often unresponsive.

Raikes says those things have prevented the foundation from reaching its full potential.

Thursday night Melinda Gates talked about the need for honest feedback from partners; Raikes talks about it too. And both say they hope the new headquarters' design, with its many informal meeting spaces and wide-open architecture, will lead to more collaboration and a richer exchange of ideas.

NPR is among the organizations that receive money from the Gates Foundation.