Permanent supported housing programs successfully house homeless adults by providing subsidized housing coupled with intensive community-based case management. The "Housing First" model of supported housing particularly has gained attention both in the United States  and abroad  as a way to address the needs of homeless clients with severe mental illness. Intensive case management, following the Assertive Community Treatment model, is not, however, likely to be needed by all homeless adults [3-4], many of whom have less serious mental illnesses or primarily have substance use disorders. Intensive case management is also expensive  and can be socially isolating and stigmatizing . In fact, one of the most common complaints of adults with severe mental illness living in independent housing is their loneliness and lack of social interaction [7-10].
The Department of Veterans Affairs (VA) healthcare system, one of the nation's largest healthcare systems, has set itself the goal of ending homelessness among veterans and has dramatically increased its funding and resources for homeless services, including expansion of the flagship supported housing program, the Department of Housing and Urban Development (HUD)-VA Supportive Housing (HUD-VASH)  program. * As the size of HUD-VASH programs increases, greater critical examination of the specific case management needs of the diverse clients served by HUD-VASH is warranted in terms of both the intensity of community-based services needed and also the potential role of group treatment approaches. Group treatment approaches have been given scant attention, although they may offer important opportunities for peer support and may improve program efficiency. Groups may foster a greater sense of community integration and encourage social integration between members while allowing case managers to meet with several clients at the same time.
Several group-based models of case management for homeless veterans have been developed within VA. One demonstration program called Peer Housing Location Assistance Groups (PHLAG)  offered homeless veterans peer support groups led by a case manager to help them find and obtain housing in the open market. The PHLAG program showed success in helping clients obtain independent housing and illustrates one approach to peer support. Another program, the Group-Intensive Peer Support (GIPS)  model, provides peer-oriented group treatment as the default mode of case management, with intensive, community-based individual case management provided only when clinically necessary. A recent study of GIPS at one VA site showed that its implementation was associated with greater social integration and faster acquisition of housing vouchers compared with other sites . However, except for the PHLAG and GIPS service models, the extent to which groups are being used in supported housing programs is not well understood.
Aside from the benefits of peer support, the potential of groups to facilitate increased contact with clients in supported housing programs needs to be examined. Groups allow case managers to provide services to multiple clients simultaneously, which can lead to more efficient care. For example, in psychotherapy, group therapy can be more cost and time effective than individual therapy [15-16]. While case management may be different from psychotherapy, the potential for providing services to groups of clients rather than clients individually may be particularly pertinent to examine as HUD-VASH programs grow and staff seek to deliver more efficient clinical services.
This study examined the current practices and attitudes regarding groups among HUD-VASH programs and case managers in the New England region, where a current project is underway to develop and disseminate the GIPS model. We examined administrative data on the use of groups in HUD-VASH and case manager responses to an online survey. …