Stephan D. Voss, MD, PhD is an Associate Professor of Radiology at Harvard Medical School and Division Chief of Oncologic Imaging and Director of Nuclear Medicine at Boston Children’s Hospital, where he also serves as Radiology Vice-Chair for Quality and Safety. Dr. Voss graduated from Princeton University and after a 2-year Fulbright fellowship at the University of Heidelberg, Germany, completed his PhD training in Human Cancer Biology and MD training at the University of Wisconsin. He completed general radiology training at the Beth Israel Deaconess Hospital in Boston, followed by Pediatric Radiology fellowship training at Boston Children’s Hospital, where he has been on the staff for more than 15 years. Dr. Voss has also been active in the multi-institutional Children’s Oncology Group, where he is a member of the Hodgkin Disease Committee, as well as Clinical Director of the COG Phase 1 Consortium Imaging Center. Dr. Voss is the author/co-author of more than 90 peer-reviewed publications and numerous chapters and review articles focused on oncology and oncologic imaging. He serves as a reviewer for multiple Radiology and Clinical Oncology publications.   Kieran McHugh, MB, FRCR, FRCPI, is the lead radiologist for pediatric oncology imaging at Great Ormond Street Hospital for Children in London, UK. Dr. McHugh graduated from University College, Galway, Ireland, and did his radiology residency in Southampton, UK. After two fellowships in pediatric radiology in Toronto, Canada, and Sydney, Australia, Dr. McHugh initially worked as a consultant pediatric radiologist at the John Radcliffe Hospital in Oxford, UK. He has since been on the staff at Great Ormond Street Hospital for Children for 20 years. Dr. McHugh has been chairman of the radiology group within the UK Children’s Cancer Study Group (UKCCSG, now CCLG) and was chairman of the British Society of Paediatric Radiology for four years. He is the sole author of onetextbook and a co-applicant on more than ten successful grant applications. He has been a central radiology reviewer on numerous European pediatric oncology trials and has authored approximately 200 peer-reviewed publications. Dr. McHugh is currently the lead section editor for pediatrics on the editorial boards of both the European Journal of Radiology and the British Journal of Radiology.