Patrick Baltzar "Pat" de Maré (also De Mare, de Mare, /də ˈmɛər/; 27 January 1916 – 17 February 2008) was a British consultant psychotherapist with a special interest in group psychotherapy. He published several works on psychotherapy.
Maré was born in London, the third son of Bror Eric August de Maré, a timber broker of Swedish origin, and his wife Ellen Ingrid (née Tellander). His elder brother was the photographer and writer Eric de Maré. He was educated at St Cyprian's School, Wellington College, and Peterhouse, Cambridge. He trained for a medical career at St George's Hospital and qualified as a doctor in 1941. He enlisted in the Royal Army Medical Corps in 1942, and was trained for Army psychiatry by Rickman and Wilfred Bion at Northfield Hospital. It was an interesting time to work as a psychiatrist: the First World War had seen ground-breaking work in diagnosing and treating trauma, and with battle casualties arriving home, Patrick de Maré had plenty of patients to look after and study. He ran an Exhaustion Centre throughout the European campaign, at the end of which he returned to Northfield Hospital, where he joined S. H. Foulkes and Tom Main in the Northfield experiment. Northfield became the centre of a series of experiments led by these eminent physicians, which studied how to deal with trauma caused by war.
After the Second World War, Maré became a Consultant Psychotherapist at St George's Hospital. In 1952 he set up the Group Analytic Society with Foulkes, and later he participated in setting up the Institute of Group Analysis and the Group Analytic Practice. He also worked with Benaim and Lionel Kreeger at Halliwick Hospital, the short-lived therapeutic community.