An experiment that began five years ago — involving multiple city and state agencies, and all 10 hospitals in Baltimore — proved so effective in keeping formerly unhoused residents in new homes that officials gathered Monday to tout funding to expand the program.

The idea pushed by housing advocates was that not everyone could be given a set of keys and expected to thrive, particularly those with serious medical conditions. They needed help with basics such as getting IDs, filing out applications, securing food and finding a ride to the doctor or a job.

The trouble was lining up money to pay for everything.

“You have to figure out how to fund the housing and how to make it available. And you have to figure out a sustainable model for funding the supportive services that are so necessary to help people find housing and keep it,” said Kevin Lindamood, president and CEO of Health Care for the Homeless, which helped spearhead the effort.

The program that emerged was named Assistance in Community Integration Services, or ACIS. City and state housing officials funded the housing, and Medicaid paid for a portion of the extras, though the federal-state health program for low-income residents doesn’t normally pay for nonmedical resources.

The catch was the city, and several counties that chose to participate, had to split the cost with Medicaid for the supportive services. The counties, including Montgomery, Prince George’s and Cecil, funded their portions themselves.

The city asked its hospitals to temporarily fund the city’s half. Officials agreed, saying they wanted to see their patients better manage chronic conditions and make fewer unnecessary trips to the emergency room.

But now, the hospitals and counties no longer have to pay. Service providers will be able to bill the Medicaid program directly for all the costs of supportive services, tapping $5.4 million included in the state budget that began July 1, said Dr. Laura Herrera Scott, state health secretary.

The program currently serves about 280 households in Baltimore and is on track to have 300 families in homes in the city. The city and three participating counties are expected to soon have about 900 families total in homes as part of the pilot. The new funding means the program can expand statewide.

Dr. Redonda Miller, president of Johns Hopkins Hospital, said the experiment was a big one when Lindamood pitched the hospitals on the program years ago. But she said the hospitals recognized the need for a collective effort to help their most vulnerable patients.

Some diabetic patients didn’t have a refrigerator to store insulin, for example. Some didn’t know how to get an appointment with a specialist or have the ability to get to the doctor’s office.

“These are the wraparound services that we united to help fund because we knew they were just as important as the housing in health care,” she said.

She cited a study of the pilot showing the program participants had far fewer trips to the emergency room and fewer hospital admissions because they were getting preventive care and better managing their chronic conditions.

That could prove significant to Maryland hospitals that have been struggling to free up bed space and reduce emergency room wait times, the longest in the country.

Maryland was the first to ask Medicaid for permission to use funding for these service extras, but Lindamood says now 18 states have followed suit and 10 more are in the process.

Mayor Brandon Scott recently supported Baltimore’s purchase of two hotels to place more people in supportive housing, and said he was looking forward to getting renovations underway.

There are an estimated 4,300 people in Maryland experiencing homelessness, half of whom are in the city.

“Housing is one of the most basic needs people can have, and it can have a dramatic impact on life and health,” he said. “We’re making strides, but we know the work is far from done.”