Alexander Y. Walley, MD, MSc, is an Associate Professor of Medicine at Boston University School of Medicine and a general internist and addiction medicine specialist at Boston Medical Center. He is the director of the Boston Medical Center Addiction Medicine Fellowship program. His research focus is on the medical complications of substance use, specifically HIV and overdose. He provides primary care and office-based addiction treatment for patients with HIV at Boston Medical Center and methadone maintenance treatment at Health Care Resource Centers. He is the medical director for the Massachusetts Department of Public Health’s Opioid Overdose Prevention Pilot Program. Since 2007, that program has trained more than 60,000 people in Massachusetts’s communities, including people who use opioids, people in recovery and their social networks. Walley graduated from Harvard College, received his medical degree from Johns Hopkins School of Medicine and received his master's degree in epidemiology from Boston University School of Public Health.