Mainstay was founded in the heart of Boston 50 years ago. Right from the beginning, the Hub has been a major focus of the programs Mainstay offers—particularly for those being treated for Severe Mental Illness (SMI). Mainstay currently operates eight programs, in 12 buildings owned by Mainstay which are spread across six neighborhoods of the City of Boston.
“Individuals served in our Boston programs are typically referred to us by the Massachusetts Department of Mental Health,” said Mainstay President & CEO Larry Oaks. “People receive services from outside agencies, which help them live in a safe and independent environment.”

Some of the Boston properties are set up as group homes consisting of individual bedrooms with shared kitchens and bathrooms. These homes are all staffed ‘round-the-clock to best support the needs of the residents. In other buildings, there are self-contained apartments with private kitchens and bathrooms and staff support during the day, as opposed to 24/7 care. “It’s critical to offer different levels of support,” said Oaks. “There is a continuum of needs when helping those with SMI.”
Over the last 50 years, Mainstay has raised capital to buy and renovate properties in Boston that are then used for supportive homes. Mainstay typically adds a new property to the portfolio every three to five years. Its most recent purchase was a six-unit house in Hyde Park that opened in 2021.
“In this sense, we are affordable housing developers,” said Oaks. “Then, when the homes come online, we manage the properties and provide services to the residents.”
The Boston properties include renovated historic homes, midsized multi-family apartment buildings, full renovated townhouse properties and several former school buildings that Mainstay renovated for use as affordable, supportive housing. Mainstay has long-standing partnerships with two of the largest human services organizations in Massachusetts: Vinfen and Bay Cove Human Services. These agencies provide supervision within the houses, case management—including oversight of medication—and access to treatment and counseling for substance abuse and mental illness.
“Working together with our partners has allowed us to provide supportive housing to some of Boston’s most vulnerable citizens for the last half century,” said Oaks. “We are proud to call Boston home.”