['To examine psychiatric morbidity, including substance use disorders, and service use in young people with experience of homelessness.', 'A cross-sectional study of 34 new residents in a supported accommodation program in Melbourne. Current and lifetime psychiatric diagnoses were made using the Structured Clinical Interview for the Diagnostic and statistical manual of mental disorders, third edition, revised (DSM-III-R). Use of psychiatric and related services was also assessed.', 'Of the 21 women and 13 men (mean age, 18.1 years; standard deviation, 2.2 years), 50% had a current major DSM-III-R diagnosis, and 82% had a lifetime DSM-III-R diagnosis. The most common diagnoses were alcohol dependence, depressive disorders and cannabis dependence. Co-morbidity was common. Few of the young people had sought or received any treatment for depressive or substance use disorders.'] Do psychiatric disorders in and service use by young homeless people?