Jill specialises in behavioural approaches to implementation science, a field which aims to identify the most effective ways to support changes in healthcare practice to improve health care and health outcomes. A particular focus is the methodological approach to the development and evaluation of complex interventions that has been developed by the UK Medical Research Council since 2000. This includes applying methods and models of behaviour change, developed largely in the field of health psychology. Jill works with multidisciplinary research teams in the UK, wider Europe, Canada and Australia. She has been involved in funded research projects to the value of around $40 million and has published around 200 papers in peer-reviewed journals.