Peter C. Whybrow, M.D., D.P.M., M.B., F.R.C.P., ACNP Fellow Emeritus, died peacefully on 25th August 2025 at his daughter’s home in Vermont, and close to his cherished family farm in Plainfield, New Hampshire, purchased while a faculty member at Dartmouth College.

Peter was born in England in 1939 and received his MD from University College London in 1962. He never truly lost his Britishness, despite moving first for a year-long residency to the University of North Carolina in 1965 and then returning permanently for a professorship at Dartmouth College in 1969. Peter was an intellectual through and through, a brilliant scientist, a caring physician and a savvy, highly respected administrator. His first administrative position was at Dartmouth College where he was Chair of Psychiatry (1971–1978), and later Executive Dean of the medical school (1980–1982). These leadership positions were extraordinary for a young physician/scientist and reflective of his exceptional administrative acumen. Peter moved in 1984 to the University of Pennsylvania School of Medicine, Philadelphia, where he led the Psychiatry Department and was a highly respected Chair. He was accepted into membership of ACNP in 1994 and contributed to the ACNP oral history of neuropsychopharmacology [1]. Peter oversaw the move of the ACNP Archives (including personal papers, oral histories, and photographs) to UCLA in 2008. They are now managed by the Center for the Study of the History of Neuropsychopharmacology at UCLA.

Peter was recruited to UCLA in 1997, where he became the Judson Braun Professor, Chair of Psychiatry, Director of the Neuropsychiatric Institute (now the Semel Institute) and Chief of the Neuropsychiatric Hospital (now the Resnick Hospital). Peter built an infrastructure that made UCLA Psychiatry thrive in its mission for research, teaching excellence and psychiatric service, consistently ranking amongst the top few psychiatric departments in the world. Under his leadership (as a sailor his term was “steering of the ship”), the grant portfolio for UCLA Psychiatry dramatically increased. Peter’s passion and insights surrounding mental health resonated with donors such as Jane and Terry Semel, Stewart and Lynda Resnick, George and Susan Soloman, Stefan and Shirley Hatos, and Michael Tennenbaum, who substantively contributed to the growth and success of UCLA Psychiatry.

In his own research on thyroid hormones and mental illness, Peter was a highly productive researcher despite his heavy administrative load (https://scholar.google.com/citations?view_op=list_works&hl=en&hl=en&user=ZGcK9d4AAAAJ). Peter’s research was in his words “to improve our understanding of the metabolic role of thyroid hormones in the adult brain, and to apply that knowledge to investigation of the pathophysiology and clinical treatment of mood disorder, especially manic-depression”. His research with colleagues including Michael Bauer and Mark Bauer (no relation) has transformed the treatment of bipolar disorder, especially in women where resistant bipolar illness is often linked to abnormality of thyroid metabolism. Not only was Peter an exceptional translational scientist but he was also a highly gifted writer and able to eloquently convey his deep knowledge of mental health and acute perception of the human psyche in a widely read trilogy of books for the public. His books “A Mood Apart” [2] “American Mania” [3] and “The Well-Tuned Brain” [4] are highly regarded, award-winning bestsellers—a tribute to his creative integration of his physician/research training and a keen observation of society.

Peter loved many aspects of life, traveling around the world (including his continued ties to Britain as Chairman of the advisory board to Centre for Eudaimonia and Human Flourishing at University of Oxford), driving old cars (his classic Morgan and older Porsche 911), caring for historic houses, such as his old New Hampshire farmhouse dating from 1777, sailing, and a passion for all aspects of his career as an academic physician/scientist. In the words of his daughter “a life lived fully”. Peter leaves many close friends and colleagues, as well as his brother and two daughters and their families. He will be sorely missed as a father, grandfather, friend, colleague, architect of several psychiatry departments, and strong supporter of mental health treatment and research both nationally and internationally.