Alastair Compston is professor emeritus of neurology in the University of Cambridge. He is a past president of the Association of British Neurologists and editor of Brain. His previous research focused on the clinical science of human demyelinating disease with contributions to the genetic epidemiology, immunology, neurobiology and treatment of multiple sclerosis. With others he writes McAlpine’s Multiple Sclerosis. His research has been recognised by several international prizes and election to Fellowship of the National Academy of Sciences of Germany, the US National Academy of Medicine, and the Royal Society of London. Now in retirement, much of his time is spent writing on the history of neurology and related topics. He will be publishing a bio-bibliography of Thomas Willis in 2021.