Yvonne qualified as a doctor and has worked in senior roles in the NHS and Department of Health and Social Care (DHSC), and in the academic and independent sectors. Between 2013 to 2019 she provided leadership for health and reduction of inequalities at city-wide level to the population of London and was Statutory Adviser to the Mayor of London.

In 2019 Yvonne was appointed Medical Director and Director of Health Protection for Public Health England where part of her job was medical leadership for the national inputs to the COVID-19 pandemic. 

Yvonne was designated the first Medical Director for Public Health at NHSE in October 2021 to develop and rebuild the public health service in that organisation.  

She has acted as an adviser to the WHO on healthy cities and continues to take a research interest in urban health and the environment.   

In 2016, Yvonne was appointed a Companion of the Order of the Bath for services to public health and in 2021 was elected as a Fellow of the UK Academy of Medical Sciences.