The Substance Abuse and Mental Health Services Administration (SAMSHA) within the U.S. Department of Health and Human Services developed this toolkit for health care providers, local communities, and patients and their families. The toolkit is a compilation of resources about both prescription and street opioids, opioid use disorder, and opioid overdose risk factors. It discusses five strategies to help prevent opioid overdose deaths, five essential steps for emergency medical personnel and healthcare professionals who respond to opioid overdoses, information for prescribers, safety advice for patients and family members, and information about recovering from an opioid overdose. A list of resources is provided for communities and organizations that are developing practices and policies to prevent opioid-related overdoses and deaths. The toolkit is also available in Spanish.