The OECD Guidelines on Measuring Subjective Well-being recommended measuring three aspects of subjective well-being: evaluative, affective and eudaimonic. However, recommendations regarding eudaimonia were tentative and reflected the lack of consensus on the concept in the literature at that time. This working paper considers different theories of eudaimonia and draws on recent advances in the field of subjective well-being to propose new working definitions for eudaimonia and eudaimonic feelings. It brings together evidence on how eudaimonic feelings lead to other desirable outcomes including long-term health and pro-social behaviour, and presents new analysis on how different aspects of eudaimonia are predicted by policy-relevant variables. It then suggests 12 elements of eudaimonia to be measured, of which four form a core set, and identifies suitable survey items to measure each. These recommendations will be submitted for consideration as a part of planned work to update the 2013 OECD Guidelines on Measuring Subjective Well-being.