This obituary honours Dr Margaret (Margie) Peden (28 January 1962–29 January 2026), a foundational figure in global injury prevention. Over a career spanning nursing, epidemiology and public health policy, Peden made transformative contributions at the WHO, where she served for 17 years as Coordinator for Unintentional Injury Prevention. Her work produced landmark global reports on road traffic injury and child injury prevention, shaped UN and World Health Assembly resolutions and established the evidence base for WHO programmes on drowning, falls and burns. She was a tireless advocate for injury prevention in low- and middle-income countries and a mentor to generations of researchers worldwide. This obituary, written by close colleagues and collaborators, reflects on her scientific legacy, her commitment to equity and the enduring human warmth that defined her professional relationships.