Paul Gissen is a Clinical Professor of Paediatric Metabolic Medicine at UCL Great Ormond Street Institute of Child Health, and Honorary Consultant Paediatric Metabolic Diseases at Great Ormond Street Hospital for Children NHS Foundation Trust. He is a NIHR Senior Investigator and leads the Gene, Stem and Cellular Therapies Theme at the NIHR GOSH Biomedical Research Centre. He is also UK Chief Investigator for a number of industry and academic sponsored clinical trials of novel therapies. Professor Gissen obtained his medical degree from the University of Glasgow and trained in paediatrics at Manchester, Sheffield and Birmingham Children’s Hospitals specialising in inherited metabolic disorders. He undertook his PhD at Birmingham University where he identified genetic causes of several rare paediatric diseases. His research interests are in developing novel gene based therapies for Rare Paediatric Metabolic Disorders.