A nationally recognized expert on homelessness and assisted housing policy, Dennis Culhane has spent more than three decades conducting research that has played an integral role in efforts to end homelessness in the United States and around the world.

“There’s been a very strong research component to how we have changed our approach to homelessness in the United States,” Culhane says. “A lot of that research is being done at Penn.”

Culhane, the Dana and Andrew Stone Professor of Social Policy in the School of Social Policy & Practice (SP2) at Penn, joined the faculty in 1990.

He says that the paradigm for ending homelessness in the U.S. has shifted. At one time, people had to successfully complete substance abuse treatment or seek help for mental health issues to begin the long and arduous process of accessing social services to secure permanent housing.

Culhane says today’s “housing first” approach to permanent residences gets people into units with no strings attached. Once they’re housed, they’re engaged in mental health services, substance abuse treatment, and have access to other support services.

And this new approach is working.

The country’s unsheltered homeless population has dropped by 26 percent since 2010. Veteran homelessness has declined even further: by 36 percent, according to the 2015 U.S. Department of Housing and Urban Development’s (HUD) Annual Homeless Assessment Report (AHAR) to Congress. Culhane is a co-principal investigator of the AHAR.

In 2009, ending veteran homelessness was identified as a major policy priority by President Barack Obama. In 2010, the administration launched “Opening Doors,” the nation’s first comprehensive strategy to prevent and end homelessness. This resulted in Congress boosting federal funding for initiatives to house homeless vets.

Culhane is director of research for the National Center on Homelessness among Veterans at the U.S. Department of Veterans Affairs (VA), “the think tank for Obama administration initiatives in veteran homelessness.”

Well before the Opening Doors initiative launch, Culhane identified two subsets of the homeless population—people who experience chronic homelessness and those who experience crisis homelessness.

Chronic homelessness involves people who have experienced homelessness for many years at a time. Crisis homelessness involves people experiencing short-term emergencies, eviction, domestic violence, sudden illness, or job loss, or reentering communities after incarceration.

When Obama announced that veteran homelessness was a priority, the Culhane-led research team was already well equipped to make recommendations.

“Evidence-based solutions have given people the ability to get out of homelessness,” says Culhane. “For people experiencing crisis homelessness, giving them a little bit of assistance often helps. People need a hand up to avoid the downward spiral.”

The decline in chronic veteran homelessness is largely attributed to the joint HUD-VA program called HUD-VA Supportive Housing.

“It provides a rental subsidy and support services to veterans who need them,” Culhane says.

Since 2009, nearly 80,000 Section-8 rental vouchers have been awarded. In addition, the VA now operates a rapid rehousing program for people experiencing crisis homelessness, serving nearly 100,000 veterans annually.

Homelessness can be solved, he says. “We know what causes it, how to mitigate the risks, and how to help people get re-housed quickly.”

Currently, Culhane is working with researchers on the “SP2 Penn Top 10 Social Justice & Policy Issues for the 2016 Presidential Election” project. He authored an essay for the project titled “Ending Homelessness Now,” which explores the tangible and evidence-based ways that the U.S. can end homelessness for both veterans and non-veterans.

Inspired by Culhane, Penn sophomore Sarah Starman, an Urban Studies major in the College of Arts & Sciences, founded the Homelessness, Outreach and Advocacy Project (HOAP).

When she took Culhane’s freshman seminar, “Homelessness and Urban Inequality,” Starman says that she realized she harbored many misconceptions about homelessness. She launched HOAP as an undergraduate club for students who seek to eradicate stereotypes about homelessness through direct service work.

Starman is part of the next generation of social justice activists, many of whom are current or former students of Culhane’s, who’ve learned how evidence-based practices along with committed resources can make a difference in the lives of those experiencing homelessness.