How to keep the U.S. safe and foil terrorists are charged issues that took a central role in last year's presidential campaign, when then-Sen. Barack Obama criticized the Bush administration's tactics. But Ms. Napolitano, in an interview this week, signaled that the Obama administration isn't contemplating a wholesale revision of the agencies or programs created under Mr. Bush to further antiterrorism efforts.

One element of Ms. Napolitano's approach, for example, will be the expansion of a pilot program started during the Bush administration to train police to report such suspicious behavior as the theft of keys from a facility that keeps radiological waste.

Ms. Napolitano also will call for deeper civic involvement and awareness to prevent attacks. She is also expected to discuss efforts to work more closely with foreign governments, from sharing airline-passenger data to intelligence about potential plots.

"We live in a world now where no one department of government can be held to be the sole repository of protecting security," Ms. Napolitano said in an interview Monday night. "There is a role to be played at every level."

But Ms. Napolitano, in a scheduled speech Wednesday to the Council on Foreign Relations in New York, is expected to emphasize the Obama administration's concern for civil liberties, a nod to voters and rights groups who supported Mr. Obama in part because they objected to elements of the Bush administration antiterror policy.

Following the speech, Ms. Napolitano will head to Ground Zero, her first visit to the site of the Sept. 11, 2001, attacks that brought down the World Trade Center towers, killing more than 2,600 people.

In an interview this week about her strategy, it was clear Ms. Napolitano's ideas aren't revolutionary, nor do they represent a sharp break from policies of the past. She isn't seeking another reorganization of the government, or even another reorganization of her department, which is the nation's third-largest with more than 200,000 employees.

Instead, she will emphasize the need to fill the sometimes large and critical information-sharing gaps that still exist among bureaucracies -- from those within her own department, to others on the federal level, down to states and local governments and the private sector. "There is a system out there," she said. "It needs to be perfected."

Some Democratic lawmakers had been critical of the DHS during the Bush administration for not working closely enough with state and local officials on counterterrorism. Ms. Napolitano's strategy aims to patch up frayed relations with other levels of government by expanding efforts to tap information and expertise in state and local agencies.

A key component of the integration efforts is a national network of roughly 70 so-called intelligence-fusion centers. They bring federal, state and local officials under the same roof to "fuse" terrorism-related intelligence.

During an intelligence briefing Monday at the U.S. Coast Guard's Puget Sound Joint Harbor Operations Center, which is in Seattle, Ms. Napolitano pressed officials from participating agencies to name a tangible benefit from the fusion centers, which they were unable to do. But in an interview later, she said she is pressing ahead to get intelligence professionals from Washington working at all the sites, which she sees as a key advance.

Some of the themes Ms. Napolitano will emphasize Wednesday also echo the findings of a private report released last year called "Homeland Security 3.0."

"While things are quiet, she does actually have an opportunity to do some forceful leadership and get things done," said James Carafano, the report's co-author. "It's much harder the day after a big terrorist attack, because then everyone wants to be in charge."

**Cam Simpson at cam.simpson@wsj.com