While many homeless persons are suffering from mental illnesses, they are often not able or willing to actively seek psychiatric treatment. in order to provide psychiatric help for mentally ill residents of facilities for the homeless in Vienna, a psychiatric liaison service for these facilities was implemented.

This study provides an overview of a six year period of psychiatric liaison services for the homeless: who was reached, which services were performed, and what support was given to staff.

Sociodemographic and diagnostic data were collected from all residents seen by the psychiatric liaison service. Liaison services provided to residents and staff were documented.

Within the six year period, liaison services were offered to 29 homeless shelters. A total of 1.808 homeless people were examined and 11.757 psychiatric services were performed. in addition to the services provided to residents, 1.471 case discussions, 1.187 supervisory services, and 857 information sessions were provided to staff. Among the examined residents, the majority were men without regular income who had been homeless for over five years. the most common diagnoses were substance-related disorders for male residents and schizophrenia for female residents. High rates of comorbidity and multimorbidity were observed. Severity of illness and low level of global functioning correlated positively with homelessness duration.

Because homeless persons rarely actively seek psychiatric treatment, the psychiatric liaison services are an important and necessary means to reach homeless persons who need psychiatric services.