William Frederic James Harkness was born on 18 March 1955 in Aldershot. He was the son of Jack Harkness, a land agent, and his wife June née Pearce. His parents ran a hotel in Anglesey which he likened to the one in the tv comedy series *Fawlty Towers*. After attending Eton School, he entered the University of Birmingham to study medicine, graduating MB, ChB in 1979. He then spent 10 years in neurosurgical training jobs, beginning at the Radcliffe Infirmary in Oxford and moving to the Birmingham Health Authority, where he was mentored by Bernard Williams and teamed up with Tony Hockley, who remained a lifelong friend. He then commenced a rotation between Atkinson Morley Hospital in Wimbledon, Great Ormond Street (GOSH) and the National Hospital for Neurosurgery and Neurology (NHNN). Travelling to North America in 1991, he spent over six months honing his skills in surgery for epilepsy at UCLA, Miami, Seattle and Montreal. When he returned from the USA and Canada, he was appointed a consultant neurosurgeon at the NHNN and GOSH. It was at the latter hospital that he was particularly to make his mark in partnership with Richard Hayward. Embracing the multidisciplinary team approach he had learnt on his travels, he worked with Helen Cross of GOSH to establish a world leading children’s epilepsy service. An exceptionally skilful surgeon, he was adept at all aspects of paediatric neurosurgery and developed a well earned reputation as an inspiring teacher. In 2014 he retired from clinical surgery, but continued his work in the field. He represented his specialty at meetings of the Society of British Neurological Surgeons and, introduced by Tony Hockley, became an enthusiastic member of the International Society of Paediatric Neurosurgeons (ISPN). In his time he served the ISPN as communications chair, scientific chair, treasurer and president from 2016 to 2017. In 2018 he was a co-founder of *InterSurgeon*, a charity providing a web-based platform by which neurosurgeons (and later other surgical specialties) the world over could communicate and share ideas. A friendly and gregarious man, he had an eclectic range of enthusiasms. These ranged from classic cars (especially his beloved Aston Martin) to art and music, from wine appreciation to travel and a fascination with history and antiques. In particular he had a great affection for Nepal, having contact with the country via a young patient and was always ready to help the Nepalese people with money and expertise, especially after the 2015 earthquake. In 1982 he married Philippa Lubomirski and they had four children Fran, Edward, Gabi and Letitia. When he died of lymphoma on 22 March 2021 aged 66, she survived him together with their children, grandchildren: Arlo, Joanie, Betsy, Peggy and Ari and his sister, Nicola.