Project Summary: The Mental and Substance Use Disorders Prevalence Study is a surveillance effort designed to produce national estimates of mental and substance use disorders among U.S. adults. The survey will include representation of household and non-household (incarcerated, institutionalized, and homeless) populations. Project Name: Mental and Substance Use Disorders Prevalence Study (MDPS). Population(s) to Be Served: The MDPS will conduct clinical assessments with adults across the United States between the ages of 18 and 65 years. The sample will include adults residing both in household (including group quarters) and non-household populations. Non-household populations will include the incarcerated (prisons, jails), institutionalized (state psychiatric hospitals), and homeless. Sampling procedures will oversample individuals at risk for mental and substance use disorders, particularly nonaffective psychosis. Strategies/Interventions: To obtain accurate estimates of mental and substance use disorders, psychiatric epidemiological surveys will be conducted from (1) a national probability household sample; (2) a national probability sample of incarcerated individuals in prisons; and (3) self-representing samples of individuals sentenced in jails and those residing in homeless shelters and state psychiatric hospitals in New York City; Seattle, Washington; and rural North Carolina. Approximately 100,000 households will be rostered to identify eligible adults to participate in the MDPS study. 56,223 individuals within households and homeless shelters will be screened to identify risk of mental or substance abuse disorders. Facility administrative rosters will be used to identify individuals residing in prisons, jails, and state psychiatric hospitals. Using screening data or facility rosters to identify respondents, trained mental health clinicians will administer clinical interviews to 8,000 individuals from the household and non-household populations. Estimates from the household and non-household samples will then be combined using statistical techniques to yield overall national prevalence estimates of seriously impairing mental and substance use disorders. Project Goals and Measurable Objectives: The MDPS will provide unbiased and precise national estimates of schizophrenia, schizoaffective disorder, bipolar disorder, major depression, post-traumatic stress disorder (PTSD), obsessive-compulsive disorder, and alcohol, benzodiazepine, opioid, stimulant, cannabis, and hallucinogen use disorders among U.S. adults ages 18 to 65.