The aim of this column is to provide an overview of the positive impacts of the Patient Protection and Affordable Care Act of 2010 (ACA) on improved health care access, quality, and outcomes for individuals with substance use disorders (SUDs), including opioid use disorders and opioid overdose deaths. Addictions nurses should be alerted to the serious, often lethal consequences that individuals with SUDs will experience if the ACA is repealed. Proposed legislation to reverse major provisions of the ACA include the American Health Care Act of 2017 (H. R. 1628), passed by the U.S. House of Representatives on May 4, 2017, and the Better Care Reconciliation Act of 2017 (H. R. 1628, Senate Amendment, June 26, 2017), which was made public just before this writing, amid much secrecy and lack of transparency. This column focuses on ACA-related Medicaid expansion and the impact that future cuts to Medicaid and other insurance coverage would have on individuals in need of SUD treatment. Finally, this column addresses the moral, ethical, and professional obligations of nurses and others involved in health care and health policy. Intensified advocacy efforts are required to ensure that recent ACA-related gains in insurance coverage and access to quality behavioral health treatment are not only preserved but also expanded. Access to health insurance coverage and health care, especially among vulnerable, high-risk populations, including those at elevated risk for opioid overdose and other SUD-related morbidity and mortality risks, is one of the most important social justice issues of our time.