Roger Trimble was born in Holyhead, Anglesey, on 19 November 1946, the son of Henry John Trimble, a farmer, and his wife Barbara Margaret, née Gill, a writer. He was educated at Bristol Grammar School and Sheffield University, where he qualified in 1969. After a series of medical and surgical posts in the Sheffield Royal Infirmary he settled on ophthalmology as his specialty and continued his training at King's College Hospital in London and at Moorfields Eye Hospital. In 1976 he was appointed consultant ophthalmologist at St Paul's Eye Hospital in Liverpool and developed his lifelong interest in the problems of squint. His book, published in 1990 jointly with Joyce Mein on *The diagnosis and management of ocular motility disorders* has become the standard text. He persuaded Liverpool University to set up a degree course in orthoptics and was made an honorary lecturer. A man of great good humour and an inspiration to young 'strabismologists', he was possessed of boundless energy at work and on the ski slopes. He enjoyed reading, theatre, walking and judo. He died, unmarried, of cancer, on 31 December 1992, aged 46.