Professor Green trained at the Royal London Hospital. Professor Green has carried out post graduate training in London, Hong Kong, Essex, Wales, Michigan (USA), Boston (USA) & Paris (France). Further specialist training has been carried out in oncology and paediatric urology at Royal Free Hospital, Michigan, Paris and Great Ormond Street Childrens Hospital.
Professor Green is a clinical lead in paediatric urology and is clinical lead in the North East London cancer network within clinical improvement.
Professor Green is a clinical lecturer in oncology for the Institute of Oncology based at Queen Mary Westfield College, St Bartholomews and Royal London Hospitals.