James William Douglas Bull, the son of a general practitioner in Buckinghamshire, was educated at Repton and at Gonville and Caius College, Cambridge, before securing an entrance scholarship to St George's Hospital Medical School and graduating there in 1936. One of his uncles was a radiologist and Bull made an early decision to specialize in radiology. In 1938 he was awarded a Rockefeller Travelling Fellowship to study newer techniques for the more precise location of brain tumours under Erik Lysholm in Stockholm. This attachment was interrupted by the outbreak of the second world war when he joined the RAMC and was posted to Malaya as a specialist radiologist with the rank of Major. For some four years after the fall of Singapore he was a Japanese prisoner of war, a period of which he later rarely spoke but which he certainly never forgot. After demobilisation he returned to Stockholm to complete his Rockefeller Fellowship. Shortly after returning to England he was appointed to the consultant staff of St George's and to the National Hospital, Queen Square, and Maida Vale Hospital for Nervous Diseases. At Queen Square he developed an outstanding department of neuroradiology, dedicated to his friend and teacher, Erik Lysholm. Thereafter, with characteristic enthusiasm and application, he remained at the forefront of development in his specialty, practising and preaching the necessity for punctuality, accuracy and precision in every aspect of his work. A handsome man, with a fine presence and a splendid voice, he was a superb lecturer and equally effective in his informal teaching. For all these reasons he became a great ambassador for Britain, ever keen to extol and support British achievements. He immediately recognised the great potential of computed tomography and magnetic resonance and spared no effort in trying to persuade British manufacturers of the vital commercial importance of these discoveries. Alas, the economic state of the United Kingdom at that time, and of British industry, deprived us of the rich fruits of many further developments in this field. Whatever may have been the failures of industry James Bull's personal influence on the training of neuroradiologists was immense; indeed, most British and many Commonwealth specialists in this field were taught by him and given loyal support subsequently. He was notably generous to his trainees and colleagues, giving strong back-up to every promising idea and full credit to its authors. James Bull's personality and mastery of his specialty inevitably led to wide honour and recognition. When Dean of the Faculty of Radiologists he served on the Council of the Royal College of Surgeons of England, and was later President of the newly founded Royal College of Radiologists. He was President of both the Radiological and Neurological Sections of the Royal Society of Medicine; President of the British Institute of Radiology, as well as founder President of the British and European Societies of Neuroradiology. He also served on the Council of the Royal College of Physicians of London and was consultant neuroradiologist to the Royal Navy. His services to his specialty were, though many thought inadequately, recognised by the award of the CBE in 1977. Bull published a number of papers on contrast myelography before his writings on computed tomography and was a contributor to Feiling's *Modern trends in neurology*. His many outside interests included golf and keeping rainfall and temperature records for the Henley-on-Thames area where he lived for many years. He also wrote a history of the building of the London to Birmingham railway. His wife Edith predeceased him in 1978 and he was survived by his son and daughter when he died on 5 June 1987.