Daniel Geller MBBS FRACP is the Founder and Director of Research at the Massachusetts General Hospital (MGH) Pediatric Psychiatry Obsessive-Compulsive and Tic Disorder (OCD/Tic) Clinical and Research Program. His research career has been devoted to the study of pediatric OCD and related disorders, their phenotypes, clinical correlates, familial patterns of inheritance, and treatment. He authored the American Academy of Child and Adolescent Psychiatry Practice Parameters for the Assessment and Treatment of OCD in Children and Adolescents, as well as the International College of Obsessive Compulsive Spectrum Disorders and Canadian Mood and Anxiety Disorders Treatment guidelines, which together document the standard of care for management of early-onset OCD in the USA and internationally. Dr. Geller is a founding member of the International OCD Genetics Consortium and received a NIMH career development award to conduct a family genetic study of pediatric OCD and subsequently assembled one of the largest cohorts of subjects ever studied, recruiting over 500 participants and publishing extensively on the findings. Early in the history of Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections (PANDAS), he was an investigator in the NIH-funded Tourette Syndrome Study group, a 2-year prospective controlled study of youth with PANDAS. Dr. Geller has been a site investigator for numerous industry and investigator-initiated medication trials since 1991 for pediatric OCD, Tourette Syndrome, attention deficit hyperactivity disorder (ADHD), and anxiety and depression, including nearly all of the original pharmacotherapy FDA registration trials for pediatric OCD. Additionally, he has been principal investigator or co-investigator in a number of NIH-funded grants, including the OCD Collaborative Genetics study. 

Dr. Geller is a triple board-certified pediatrician, psychiatrist, and child psychiatrist, a Distinguished Fellow of the American Academy of Child and Adolescent Psychiatry, Fellow of both the American and European College of Neuropsychopharmacology, and an executive board member of the International College of Obsessive Compulsive Spectrum Disorders. He is the recipient of several honors and awards in medicine and developmental pediatrics, notably from the American Academy of Child and Adolescent Psychiatry, Obsessive-Compulsive Foundation and Tourette Syndrome Association. Since 2013, he has held the Mittelman Family Chair in Child and Adolescent Psychiatry at MGH. Dr. Geller is a Professor of Psychiatry at Harvard Medical School and continues to teach, provide clinical care, and conduct research with a focus on OCD, anxiety disorders, and Tourette's Syndrome in youth.