Jose Luis Calleja is head of the Gastroenterology and Hepatology Service at the Puerta de Hierro University Hospital and is a Professor of Medicine at the Autonomous University of Madrid. He received his bachelor’s degree in medicine and his Ph.D. from the Autonomous University of Madrid. He has participated in the Spanish National Hepatitis Plan since 2015 and is an active member of the Hepatitis C Observatory of the Community of Madrid. He has been involved in the development of the most important registry in hepatitis C treatments (Hepa C), being the director of this registry until 2018. He is a member of the board of directors of the Spanish NASH registry (HEPAMET). He is also part of the National Consensus on Diagnosis and Management of NAFLD. He is president of the Spanish Association for the Study of the Liver (AEEH). He leads one of the most active research groups in hepatology in Spain. He is the current deputy director and member of the board of directors of the Instituto de Investigación Sanitaria Puerta de Hierro (IDIPHIM) in Madrid. His research interests focus on the digestive system.