Abstract
Psychiatric illness is overrepresented among the homeless, but mental health services are underutilized in this population in proportion to their needs. The current study was concerned with 900 homeless men and women randomly sampled and systematically interviewed with the Diagnostic Interview Schedule; it focuses on psychiatric and substance abuse rehabilitation service patterns and stated needs of this population in relation to specific psychiatric disorders. Although rates of lifetime treatment utilization were fairly high in comparison with general population utilization patterns, rates of treatment in the current year were low. In particular, outpatient services have been neglected for reliance upon inpatient services. Although the major reason cited for not obtaining treatment by homeless persons with mental illness was lack of insurance and inability to pay for it, having health insurance was not associated with mental health services utilization, nor were other important predictors apparent. Mental health professionals serving mentally ill homeless populations would best serve them by focusing on creative and innovative ways to improve the availability and attractiveness of ambulatory care services.