NIDA is a federal scientific research institute under the National Institutes of Health, U.S. Department of Health and Human Services. NIDA is the largest supporter of the world's research on drug use and addiction. NIDA-funded scientific research addresses the most fundamental and essential questions about drug use, including tracking emerging drug use trends, understanding how drugs work in the brain and body, developing and testing new drug treatment and prevention approaches, and disseminating findings to the general public, researchers, policymakers, and others.