Professor Klara M. Posfay-Barbe is one of the co-chairs of ESPID 2021. She is a member of the Pediatric Infectious Diseases Group of Switzerland (PIGS) and, of course, of ESPID. She is the current Head of the Division of General Pediatrics and of the Pediatric Infectious Diseases Unit at the Children’s Hospital of Geneva, part of the University Hospitals of Geneva (HUG), Switzerland. She is a Professor at the University of Geneva’s Faculty of Medicine since 2014. She is also the Deputy Medical Director of the University Hospitals of Geneva (HUG). She is the Director of the Clinical Research Platform in Pediatrics, Gynecology & Obstetrics, and is the current President of SwissPedNet, the association of all pediatric clinical research centers of Switzerland. She is a member of the Swiss Academy of Medical Science. Formerly, she was the President of the Medical Society of Geneva and of the Ethics Committee in Pediatrics, Gynecology & Obstetrics in the state of Geneva. Her major research interests are immune responses in immunocompromised hosts, including responses to vaccines, detection and management of viral and bacterial infections, especially in transplant recipients, and host-pathogen interaction.