This note considers the role that demography as a discipline can play in addressing some of the key questions in the context of human wellbeing and sustainable development. Starting with the wellbeing function of sustainability science that tries to explain an indicator of human wellbeing as being determined by a set of capitals and explanatory factors, it gives an example of how the constituents of such a wellbeing indicator can be combined based on a demographic approach. It also highlights how a broadened view of demographic methodology that goes beyond the conventional focus on age and sex alone can help to make demography more relevant for studying the key challenges of humanity.