Dr Williams is a Senior Clinical Research Fellow at the University of Edinburgh, and an Honorary Consultant in Paediatric Respiratory Medicine at the Royal Hospital for Children and Young People, Edinburgh. Since 2019 he has worked with the World Health Organisation on their RSV Global Surveillance Programme, and is currently an honorary consultant for the United Kingdom Health Security Agency’s Respiratory Virus Unit. In 2021-2022 He led the BronchStart study , which provided detailed estimates of RSV disease burden to inform the decision to implement RSV maternal vaccination in the United Kingdom. This winter (2024-2025) Dr Williams led the BronchStop study, which aimed to understand the effectiveness of this newly introduced RSV maternal vaccine, and potential barriers to update.