Persons with severe mental illness, particularly those with a history of comorbid substance use disorders, have a highly elevated risk of HIV, hepatitis B, and hepatitis C infection. However, most clients with severe mental illness do not receive basic best-practice services such as prevention, early detection, and effective treatment of these diseases. Stanley Rosenberg, Ph.D., and his colleagues describe a public health model intervention designed to deliver basic best-practice services for blood-borne diseases to clients with severe mental illness and co-occurring substance use disorders. The brief intervention, called STIRR (screen, test, immunize, reduce risk, and refer), is delivered at the site of mental health care by a mobile team of specialists. The authors also describe a pilot study to evaluate the STIRR model in two publicly funded community mental health centers, the results of which are promising (see page 660).