For Megan Bergbauer, her first years out of the Marine Corps were tough.

After serving three years at Camp Pendleton, near San Diego, Bergbauer, now 30, moved back to Ambler in 2010 with a young daughter, marriage problems, and no job.

"You go into the military and they pay for your housing, they pay for your food," said Bergbauer, a former field radio operator and mail clerk in the Marines. "Then you're out, and if you don't find a job, it's like, 'Uh-oh.' Then what?"

She stayed with relatives and sometimes slept in her car. Bad turned to worse. Bergbauer cycled in and out of shelters, even sleeping for two weeks in LOVE Park in Center City.

"It was a nightmare," Bergbauer said.

A national nightmare, as it turns out.

Each year, about 150,000 veterans become homeless - about one in 10 former military men and women, said Dennis Culhane, an expert on homelessness at the University of Pennsylvania.

Many are dealing with combat trauma, while others are struggling to find work with skills that do not necessarily translate into today's workforce, he said.

So high is the representation of former soldiers among the nation's homeless that President Obama pledged in 2009 to end homelessness for vets by 2015.

To reach that goal, the Department of Veterans Affairs has enlisted the help of Culhane and a think tank he helped to launch in Philadelphia.

The National Center on Homelessness Among Veterans, located near the VA Medical Center in West Philadelphia, was started in 2009 to study the dynamics of homelessness among veterans, as well as the best ways to help them.

With an annual budget of $2.3 million from the VA, the center has about 20 employees, including 12 full-time researchers, and collaborates with partners at VA medical centers in Tampa, Fla., and Bedford, Mass.

Vincent Kane, the organization's executive director, said ideas coming out of the center have helped to steer how the VA spends money on homelessness across the country.

A core recommendation is the belief that the best way to help the chronically homeless is to provide them with permanent housing and supportive services.

Such a "housing-first" approach has been "a game changer," Kane said.

Every January, the Department of Housing and Urban Development conducts an annual spot check of homeless people living in shelters and on the streets. In 2009, it counted 75,609 homeless veterans; in 2013, the number was down to 57,849.

Many vets who are chronically homeless suffer from mental illness, addiction, or both. Kane said that for so long, the thinking inside the VA was to treat the underlying problems and let the housing component work itself out. Too often, however, people languished in shelters or on the streets.

Today, the emphasis is on moving people immediately into housing, then directing them to medical, behavioral, and other services available in the community, he said.

While some veterans will need such long-term help, others will require only triage funding, such as a few months' rent, to avoid homelessness, Culhane said.

This year, Culhane said, the VA will help about 80,000 vets and their families with short-term rental help, known as "rapid rehousing." An additional 60,000 people will get rental subsidies for permanent housing, plus supportive services.

"Those are the two most effective programs," Culhane said.

In both areas, Congress has increased spending. In 2009, the VA spent $400 million on homeless programs, helping about 30,000 vets. In 2013, the agency earmarked $1.4 billion for helping about 170,000 vets.

In Philadelphia, a coalition of nonprofit service providers works with the VA to address the local needs of veterans.

Bergbauer got help from Pathways to Housing PA, a housing-first specialist that has been operating in Philadelphia for five years. The agency works with 130 vets, about half of whom are younger men and women from the Iraq and Afghanistan conflicts, said Christine Simiriglia, executive director of the local office of Pathways.

Once a person is placed in an apartment, a Pathways team - including a nurse, social workers, and a psychiatrist - steers the client to existing services and help in the community, she said.

Before Bergbauer was placed in an apartment, she had been living in a Montgomery County shelter on the grounds of Norristown State Hospital.

She qualified for a VA rent subsidy and used it to lease a two-bedroom apartment in West Philadelphia. Housed since October 2012, Bergbauer has a caseworker with Pathways who checks up on her and offers help if she needs it.

Bergbauer, who has a 6-year-old daughter, gave birth to a son two months ago. She said the work experience she gained in the military as a radio operator was not easily transferable to the private sector. She had been taking courses at Drexel University and would like to eventually return to study forensic science.

"I definitely needed the help," she said. "I would have been in deeper trouble."

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