Basil underwent his initial postgraduate training in Manchester and obtained MRCP (UK and Ireland) in 1992. His endocrine and diabetes training commenced when he took up a registrar post as part of the Wessex rotation. He further pursued his career in this subspecialty as a clinical research fellow at the University of Wales, College of Medicine where he completed his MD thesis titled "Mechanisms underlying hypothalamic desensitisation in the diabetic GK rat".
He was appointed senior registrar at the University Hospital of Wales in 1996 before taking up his consultant post in Manchester. He was awarded FRCP in 2002. He has held a number of leadership posts in the NHS including being clinical director of medical specialties and associate medical director. He has an active research interest in low energy diets, adrenal disease and diabetes in pregnancy.