A public television executive at New York’s Thirteen/WNET and WLIW New York, Paula Kerger, was named president and chief executive of the Public Broadcasting Service yesterday, where one of her key challenges will be maintaining the organization’s decentralized structure while unifying its stations to strengthen the enterprise.

Success, she said, depends on “the ability to get the staff at PBS as well as the [station] leaders across the country to stand together,” Ms. Kerger told the Associated Press.

The national nonprofit with a $300 million annual budget acquires and distributes programs such as “Nova” and “Masterpiece Theater” on behalf of 348 public television stations that vary widely in size and scope.

The appointment of a seasoned executive from within the ranks is part of an ambitious expansion plan into “areas that are underserved,” Ms. Kerger said.

The chairman of the PBS board, Mary Bitterman, told The New York Sun: “We want to be the helpmate of the nation.” She proposed four program themes: early childhood education, literacy, civic engagement, and preparing communities for disaster.

These areas would not replace PBS’s commitment to arts, science, public af fairs, and children’s programming, she said. “What we’re talking about is honing in and refining,” Ms.Bitterman said.

The idea would require increased funding, in part to expand local stations’ digital and Internet distribution.

“We would like a very significant increase in our budget,” Ms. Bitterman said.

She said Ms. Kerger is well qualified for the fund-raising challenges ahead of her. Ms. Kerger led a $79 million capital campaign for Thirteen, bringing in major philanthropists such as Lewis Cullman as donors.

“She’s thorough, hands-on, a great listener. It’s a big loss to Thirteen and she will be missed,” Mr. Cullman, who supports the arts program Egg, said.

Ms. Kerger has already started bringing her talents to bear on a national level. As a founding trustee of PBS Foundation, formed last year to raise private funds, Ms. Kerger helped to secure $13 million. In this capacity, she also demonstrated her sensitivity to the sovereignty of the member stations by establishing a station advisory group that developed protocols for solicitation.

“It wasn’t that the foundation was launched, and people got upset. That didn’t happen because Paula thought about it ahead of time,” Ms. Bitterman said.

The executive director of the Center for Digital Democracy, Jeff Chester, told the Associated Press that Ms. Kerger has her work cut out for her.

“On the one hand, she has to stay strong to her principles and resist pressure from conservative critics. But she also has to appeal to those critics to get them to support a blueprint for the future,” Mr. Chester said.

Ms. Kerger came to the Educational Broadcasting Corporation from the fund-raising juggernaut the Metropolitan Opera, first working in fund-raising and then assuming other management responsibilities. She rose to the position of chief operating officer at Thirteen in 2004 after serving as station manager.

“She’s an effective proponent and explainer of the values of public service broadcasting,” Ms. Kerger’s current boss, the chief executive of the Educational Broadcasting Corporation, William Baker, said.

New Yorkers may already know Ms. Kerger from her on-air appearances. “Hi I’m Paula Kerger, Thirteen’s chief operating officer with an urgent message,” Ms. Kerger said during a pledge drive in June.

Ms. Kerger, 48, will move to Washington, D.C., to assume her new position starting March 13. The outgoing chief executive of PBS, Pat Mitchell, will head of the Museum of Television and Radio.