Barry R. Davis, MD, PhD, is a physician-scientist, professor emeritus, and the former Guy S. Parcel Chair in Public Health at the University of Texas School of Public Health. He has helped lead landmark clinical trials that reshaped the prevention and treatment of cardiovascular disease, including studies that informed national and international guidelines. Drawing on this experience, Davis explores how early warnings are recognized or ignored and why prevention remains one of society's most powerful yet underused tools.