Hilary Dawn Cass is a British paediatrician known as chair of the British Academy of Childhood Disability, for establishing the Rett Clinic for children with the Rett syndrome neurodevelopmental disorder, for developing palliative care for children, as well as for leading the Cass Review completed in 2024. In the 2024 Dissolution Honours, Cass was nominated for a life peerage as a crossbencher.