Together with Consulting Editor, Dr. Helen Bucher, Guest Editors Dr. Carlos Del Rio and Dr. Sandra Springer have put together an important monograph that addresses infections in IV drug users. They have selected top experts to contribute clinical reviews for infectious disease physicians. Articles are devoted to the following topics: Medical and Surgical management of Infectious endocarditis in persons who use drugs; The Microbiology Laboratory and the Opioid epidemic; The Geography of Infectious Diseases Related to the Opioid Epidemic; Soft tissue, bone and joint infections related to illicit drug use; Management of opioid use disorder and infectious disease in the inpatient setting; Outpatient antimicrobial and OUD management in persons who use drugs; Novel approaches to antimicrobials for injection drug use associated infections; HCV treatment and reinfection risk in persons who use drugs on medication treatment for OUD: A systematic review in CJS settings; Treating opioid use disorder and related infectious diseases in the criminal justice system; Harm reduction services to prevent and treat infectious disease in persons who use drugs; Improving the management of patients with chronic opioid therapy in the outpatient setting; The Global Task Force for Chronic Pain in People Living with HIV (PLWH): Developing a research agenda in an emerging field; and Lessons learned from the response to the HIV epidemic that can inform addressing the opioid epidemic. Readers will come away with the clinical information they need to treat and improve outcomes in these patients.