Mark’s research and professional activity is about making significant contributions to the evidence base for oral health and its interface with general health and wellbeing with particular emphasis on vulnerable and marginalised people. Professor Gussy has experience and academic success that transcends professional boundaries and is now firmly located in transdisciplinary action and rural and community-centred health. Mark has strength in research methods, including trials, longitudinal cohort and prospective repeated cross-sectional design, together with a clinical interest in clinical disease and its multiple determinants, leading his research work towards complex community intervention trials and birth cohort studies. Mark has a particular interest and experience of systems of care/treatment services and the people and groups that sit outside the mainstream service and social systems and the health and social inequity that arises from this. Expert in oral health and its use as a vehicle for exploring broader social and structural determinants of participation and also challenging entrenched, exclusionary systems that disadvantage the most vulnerable. His work is multidisciplinary and straddles multiple domains including clinical care, health service research, community and participatory research, and equity and inclusion.