Department of Justice: Office of Justice Programs (OJP)
https://www.ojp.gov 
The Office of Justice Programs (OJP) provides innovative leadership to federal, state, local, and tribal justice systems, by disseminating state-of-the art knowledge and practices across America, and providing grants for the implementation of these crime fighting strategies. Because most of the responsibility for crime control and prevention falls to law enforcement officers in states, cities, and neighborhoods, the federal government can be effective in these areas only to the extent that it can enter into partnerships with these officers. 
 
 

Department of Health & Human Services (HHS): Substance Abuse Mental Health Services Administration (SAMHSA) 
https://www.samhsa.gov/
The Substance Abuse and Mental Health Services Administration (SAMHSA) is the agency within the U.S. Department of Health and Human Services that leads public health efforts to advance the behavioral health of the nation. SAMHSA's mission is to reduce the impact of substance abuse and mental illness on America's communities. SAMHSA promotes and implements prevention and early intervention strategies to reduce the impact of mental and substance use disorders in America’s communities. 

• Center for Substance Abuse Prevention (CSAP) -- The mission of the Center for Substance Abuse Prevention is to improve behavioral health through evidence-based prevention approaches
• Center for Substance Abuse Treatment (CSAT) -- The mission of the Center for Substance Abuse Treatment is to promote community-based substance abuse treatment and recovery services for individuals and families in every community. CSAT provides national leadership to improve access, reduce barriers, and promote high quality, effective treatment and recovery services

Centers for Disease Control & Prevention (CDC)
https://www.cdc.gov/ 
CDC remains committed to advancing a public health approach to preventing drug overdose death and applies its scientific expertise to help curb the epidemic in three ways: improving data quality and surveillance to monitor and respond to the epidemic; strengthening state efforts by scaling up effective public health interventions; and equipping health care providers with the data and tools needed to improve the safety of their patients