Obituary: Prof. Dan Joseph Stein (1962 - 2025)

It is with deep sadness that we share the news of the death of Professor Dan Joseph Stein, MD, PhD, who passed away on Saturday, 6 December 2025, at the age of 63. His loss is felt profoundly as we remember an exceptional psychiatrist — both clinically and scientifically — as well as a remarkable colleague and friend.

Professor Stein was Full Professor and Chair of the Dept of Psychiatry and Mental Health at the University of Cape Town (UCT), Director of the South African MRC Unit on Risk & Resilience in Mental Disorders, and Scientific Director of the UCT Neuroscience Institute. Additionally, he was a Visiting Professor at Mount Sinai School of Medicine in New York and at Aarhus University in Denmark. Within the World Psychiatric Association (WPA), he served as Chair of the Section “Anxiety and Obsessive-Compulsive Disorders” and represented one of the 10 WPA Collaborating Centres.

Professor Stein was a global leader whose influence spanned clinical practice, rigorous research, and intellectual philosophy. His legacy is one of expansive knowledge, deep compassion, and unwavering collaborative spirit. Professor Stein’s scientific contributions focused on the psychobiology and treatment of anxiety-related conditions, obsessive-compulsive disorder and post-traumatic stress disorder. Foundational work on Obsessive-Compulsive and Related Disorders (OCRDs) stands as an enduring contribution to clinical psychiatry. He championed the OCRD category in modern nosology, chairing the workgroups for both the DSM-5 and ICD-11 on these disorders. This leadership ensured the evidence-based separation of OCRDs from anxiety, fundamentally reshaping our diagnostic and research paradigms.

With doctoral degrees in both clinical neuroscience and philosophy, Professor Stein’s intellectual breadth was remarkable, influencing volumes like The Philosophy of Psychopharmacology. His body of work—more than 1,600 peer-reviewed papers and over 25 authored or edited books—places him among the most widely cited researchers across the globe. His clinical and neurobiological investigations included: Co-leading the ENIGMA-OCD and ENIGMA-Anxiety workgroups, which pooled global data to identify structural and functional brain correlates of these conditions; Leading and contributing to numerous trials and Cochrane systematic reviews on pharmacotherapy and psychotherapy for OCD, PTSD, trichotillomania and social anxiety disorder; Serving as a Director of the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS), a commitment honoured by the dedication of the recent CANMAT-ICOCS International Guidelines for the Management of Obsessive-Compulsive Disorder to his memory.

Professor Stein was deeply committed to advancing research and care in low- and middle-income settings. He returned to South Africa from a fellowship in psychopharmacology at Columbia University to dedicate his career to this mission. At UCT, he was the Director of the early Brain and Behaviour Initiative and the inaugural Scientific Director of the Neuroscience Institute, the first of its kind on the African continent. He initiated the South African MRC Unit on Anxiety & Stress Disorders, which undertook the first nationally representative community survey of mental disorders on the African continent, as part of the World Mental Health Surveys. He founded and served as the first President of the African College of Neuropsychopharmacology. He led initiatives, like the Neuro-GAP study, which focused on the genetics of schizophrenia and bipolar disorder in African populations, promoting crucial diversity in psychiatric genetics research. As Chair of the World Psychiatric Association Scientific Section for Anxiety and Obsessive-Compulsive and Related Disorders, he promoted science of the highest quality to tackle contemporary global mental health challenges and inequalities. He chaired the Lancet Psychiatry Commission Global Action on Problematic Usage of the Internet and edited the textbook Mental Health in a Digital World.

Over the course of his career, Professor Stein received numerous honours, among them the Lifetime Achievement Award from the World Federation of Societies of Biological Psychiatry, the Max Hamilton Memorial Award from the International College of Neuropsychopharmacology, the John F. Herschel Medal from the Royal Society of South Africa and the SAMRC Platinum Award for research excellence.

Yet, for those who knew him, his scientific achievements were rivalled by the warmth of his friendship and the depth of his character. Dan was a sensitive, thoughtful, kind clinician and an exceptional leader who nurtured staff and scientists from all backgrounds. His greatest love was for his wife Heather, his children and a first grandchild, of whom he was exceptionally proud. He fostered a vibrant, human connection within the research community that transcended the data and the papers.

Dan Joseph Stein’s friendship, quiet determination, curiosity, and boundless brilliance will be profoundly missed. We remember him not only as a giant in psychiatric research, but as a wonderful friend who left us too soon. We join the global community in being deeply shaken by his death and in extending our heartfelt condolences to his family, friends, colleagues, students and all who had the privilege of knowing or collaborating with him.