This training will provide information on the consequences of substances commonly used by consumers and will introduce participants to the epidemiology and prevalence, and neurobiology of co-occurring disorders. Substance use disorder (SUD) is a diagnostic term referring to recurrent use of alcohol or other drugs (AOD) that causes “clinically and functionally significant” impairment, i.e., work, school, home, and health. Addiction is a term used to indicate the most severe, chronic stage of SUD, when there is substantial loss of self-control, indicated by compulsive drug-taking despite the desire to stop using the substance. This training will explore the neurobiological basis of SUDs and provide information on the medical consequences of substance use.