Griffiths has practised as a service based public health physician at local, regional and national level in the UK, and worked as a senior academic in Hong Kong. Completing public health training in 1985, she became a senior registrar in Hackney where she pioneered community health partnerships before moving to Oxford as a consultant in public health in 1998. In 1990, Griffiths became the youngest Regional Director of Public Health when she was appointed to South West Thames Region. On reorganisation of London's health services, in 1993 she returned to Oxford as Oxfordshire's Director of Public Health. Whilst Co-Chair with Lord Hunt of Kings Heath, of the Association of Public Health, she co-founded the UK Public Health Association. A member of the Board of the Faculty of Public Health, Griffiths was elected President of the Faculty in 2001. Griffiths was an adviser to the Department of Health on the Choosing Health White Paper and investigated the health of rough sleepers for
Dame Louise Casey and the regulation of doctors for the GMC. As President of the Faculty of Public Health, Griffiths was in Hong Kong in March 2003, when the
SARS epidemic broke out. Quarantined on her return to the UK, Griffiths went on to co-chair, with
Sir Cyril Chantler, the Hong Kong Government's SARS Inquiry. The SARS Inquiry Report resulted in a strengthening of disease surveillance in Hong Kong and southern China. In 2005, Griffiths was invited back to Hong Kong to take up the position of Director of the School of Public Health and Primary Care at the
Chinese University of Hong Kong (CUHK). Over the next few years she developed new academic programmes for CUHK, including the first BSc in public health in Hong Kong, built educational and research links throughout mainland China, in North America, UK, the Middle East, SE Asia and Australia, She is the founding Chair of the Centre for Global Health which incorporates the work of the
Collaborating Centre for Oxford University and CUHK. Since returning to the UK in 2014, Griffiths has maintained her teaching and research links with Hong Kong, becoming an Emeritus Professor at CUHK, Senior Advisor to the CUHK Vice Chancellor on International Academic Developments between 2014 and 2018 Current roles include Non-Executive Board member of
Public Health Wales,. She was Associate Non Executive Board Member of
Public Health England and Chair of the Global Health Committee, until its demise and between 2017 and 2025 was Trustee, Deputy Chair and then Chair of Gambleware. Following the outbreak of COVID-19, Griffiths' public health knowledge and experience of the SARS epidemic have been regularly drawn upon in the media in UK and abroad. == Honours and awards ==