Today, the U.S. Department of Health and Human Services released a report showing that states can greatly improve access to behavioral health services for residents by expanding Medicaid under the Affordable Care Act. Substance use disorders and mental illness are prevalent and serious public health problems in American communities. According to today’s report, in 2014, the most recent year for which data is available, an estimated 1.9 million uninsured people with a mental illness or substance use disorder lived in states that have not yet expanded Medicaid under the Affordable Care Act and had incomes that could qualify them for coverage.