Three major Boston hospitals announced a $3 million partnership Wednesday aimed at increasing housing stability among Greater Boston’s renters and urged the commercial housing industry to join their efforts.

Boston Medical Center, Boston Children’s Hospital and Brigham and Women’s Hospital will invest nearly $3 million over three years into housing stability through the Innovative Stable Housing Initiative (ISHI), a pilot project with the goal to identify, assess and fund strategic approaches to increase housing stability for Greater Boston’s most vulnerable populations.

“Often, what patients need to become healthy is not medical treatment, but a prescription for the root cause of what is preventing them from getting well, like housing,” Thea James, vice president of mission and associate chief medical officer at Boston Medical Center, said in a statement. “This collaboration between Boston Medical Center, Boston Children’s Hospital and Brigham and Women’s Hospital will help address the housing disparities that many of our patients and neighbors face on a daily basis. By partnering with community organizations and residents who are most often left out of decisions and most at risk for displacement to be part of the decision-making process, we can make a measurable difference in the health of communities.”

The effort is part of a larger shift in medical thinking, BMC housing and health researcher Dr. Megan Sandel told Banker & Tradesman.

“As a health sector we’re recognizing stable housing as a key driver of health outcomes but we also know we won’t solve this problem ourselves,” she said. “We’re trying to contribute in interesting ways to prevent eviction, to prevent displacement, to create more affordable housing and work with other sectors like banks and businesses.”

More area hospitals are looking to use their charitable giving as an investment in increasing affordable housing, she said, in an effort to “work upstream” of illnesses and other health problems they treat.

“We have people who are medically fragile, homeless who are very high utilizers of health care system. In our Medicare population, of our top 2 percent of patient cost people, 40 percent are homeless or housing unstable,” she said. “That being said, we also recognize it’s important to have stable housing as a child when you’re learning and growing. It helps you stay in school, it helps your parents stay in work and keeps you happy and healthy.”

In the case of the ISHI, each hospital’s investment is part of an agreement with Massachusetts Department of Public Health’s Determination of Need Community Health Initiative. Under that program, BMC alone has an obligation to give away $6.5 million to improve health in the community.

To streamline its work, ISHI is comprised of three funds. The first is a “flex fund,” supported by all three hospitals, which will fund a variety of strategies, including funds to help low-income residents with apartment down-payments and lawyers if they are facing eviction. Consultation with community groups showed that existing funds for housing stabilization were insufficient to meet the need and eligibility criteria often limited access for residents experiencing housing instability, BMC said in a statement. After a thorough RFP review process, three organizations, Casa Myrna Vasquez, Urban Revival and Homestart have been selected and will receive grants totaling nearly $500,000 for one year.

The second is a “upstream fund” supported by $1 million from Boston Medical Center and Boston Children’s, which “strives to support policy and systems change efforts around stable housing,” BMC said. The third is a smaller amount of money, provided by Boston Medical Center alone, which aims to engage Boston’s working-class people of color to design a separate, resident-led grant-making process without input from the hospital. This effort will work with the Center for Economic Democracy, Boston Ujima Project and Right to the City.

Sandel said BMC is actively talking with other housing investors to increase investments in affordable housing. She said she hopes members of the broader commercial housing industry, including landlords, join in the effort, and rejected the idea that pushing eviction protections and other policy changes automatically put them on a collision course with commercial landlords.

“I think this is a story of ‘we.’ We all benefit when neighborhoods are stable and people are able to put down roots,” she said. “The analogy I always use is that a tree always grows strongest and tallest when it has deep roots. We are working with the housing sector in this space because we need a balanced approach. We haven’t built enough affordable housing in the last three to four decades and this is the health sector recognizing that.”

BMC hopes to release a more specific vision statement that details its housing policy change goals later this fall, Sandel said.