The Substance Use x Chronic Conditions Lab is based within the Division of Geriatrics, Gerontology, and Palliative Care in the Department of Medicine at the University of California San Diego. We aim to address the growing prevalence of substance use (alcohol, cannabis, sedatives, hypnotics, illicit drugs) among older adults and adults living with multiple chronic diseases. The lab employs a public health and harm reduction lens to reduce the harms of unhealthy substance use among a diverse population of older adults. Our research group conducts a range of research studies, including epidemiological, health services, and the development and testing of interventions that focus on the intersection of substance use, chronic disease, and aging.