This Festschrift provides important and valuable guidance on population oral health. It is unfortunate that it coincides with the retirement of one of population oral health's pioneers, Professor John (AJ) Spencer, who has made significant contributions to the subject over the last 35 years. Oral diseases and disorders remain prevalent and have detrimental effects on individuals, and society-at-large. Many of our attempts to improve population oral health through existing oral health services have met with limited success, owing to the focus on ‘care’ rather than ‘cure’. It has long been recognised that oral diseases are largely behavioural in origin; but this approach at the individual level has not been entirely successful. There is a need to consider ‘mid- and up-stream’ approaches to changing oral health and health care delivery systems. However social inequalities are a major determinant of oral health, and their influence in oral health are omnipresent, which emphasises the important role of population oral health in future health care strategies. The Festschrift provides theoretical and empirical evidence of the need for further epidemiological investigations (particularly life course studies), innovative approaches to oral health surveillance and oral health outcome evaluation, plus a realisation that multidisciplinary approaches are the way forward. In an information and globalization era, we must put the ‘population’ into oral health and this is our challenge for the 21st Century.