Age UK wants older people to make the most of later life. We define those who are able to make the most of later life as having high wellbeing. And measurement of whether older people in the UK are able to maximise their wellbeing is important to understand who is experiencing low wellbeing and why. Our construction of an Index of Wellbeing in Later Life, using Understanding Society data, allows us to identify these individuals and the determinants to wellbeing. And importantly, our measure of wellbeing encompasses all the domains of life including personal, social, health, resources and local. In this way, we can explore how the domains of life are interconnected. These interconnections emphasise the importance of person-centredness in supporting older people. In this session, we will showcase the methodology used to produce the Index, what it tells us and how Age UK will use it in its work.