Dr. Keith Humphreys is a professor of psychiatry and behavioral sciences at Stanford School of Medicine and a leading expert on treating addictions, drug laws and policy. We discuss all the major addictive substances and behaviors, including alcohol, opioids, gambling, stimulants, nicotine, cannabis and more, focusing on how genetics and certain use patterns shape addiction susceptibility. We discuss the best evidence-based tools for recovery, from 12-step programs to emerging treatments such