Substance Abuse and Mental Health Services Administration (SAMHSA) | 400,053 followers on LinkedIn. In crisis? Call/text 988 or chat 988lifeline.org. Treatment for mental and substance use disorders: findtreatment.gov | The Substance Abuse and Mental Health Services Adminstration (SAMHSA) is the agency within the U.S. Department of Health and Human Services (HHS) that leads public health efforts to advance the behavioral health of the nation. Charged with reducing the impact of substance abuse and mental illnesses of America's communities, SAMHSA has made significant strides throughout its 22-year history and serves as a national and global leader in the field of behavioral health care.