Diffraction is a mapping of interference, not of replication, reflection, or reproduction. A diffraction pattern does not map where differences appear, but rather maps where the effects of difference appear. (Haraway 1992:300). When we describe worlds in certain ways we simultaneously create them; they do not pre-exist but are effects of our interference. Diffraction is an analytical strategy that maps the material-semiotic effects of such interferences. At a two-day seminar in Copenhagen, 22-23 September 2016, we wish to diffract ageing through the prism of energy. In the application for Centre for Healthy Ageing II we stated that ‘(a)n important golden thread running through the different [societal and individual] levels has turned out to be “energy” and retention of energy in its broadest sense, for life and society’ (p.4). While energy in Theme I hitherto has received only scarce attention due to the fact that there is only scant empirical and theoretical work available on energy in ageing studies. Yet, across the board of our ethnographic fieldwork experiences, the theme of energy looms large and we therefore wish to probe the relationship between ageing and energy a bit further. We aim to do so in a two-day seminar for researchers in Theme 1 in tandem with a small crowd of invited, external researchers, whom we ask to act as expert commentators and facilitators of the diffraction process. When ageing is diffracted through the prism of energy, many different facets of ageing come to the fore. At the seminar we wish to illuminate several of these facets and discover their differences and their effects. Although old age and energy seem to be juxtaposed - they could at the same time be seen to be welded together. So while energy usually pertains to youth, and old age is often associated with mental and physical decline and a lack of energy, the focus in recent decades on positive qualifications of the ageing process – successful, healthy and active ageing – has helped nuance the simplified image. The diffracted consequences of ageing and energy tell different tales of what could be called ageing-energism – the occasions where ageing and energy co-exist in reinforcing, interfering or interacting ways. To help our thinking – to nourish the prism - we invite different speakers from disciplines and fields who work with energy in ways that are rather alien from our’s (physicists, engineers, biogerontologists and healers). By doing so, we hope to accomplish a collective diffractive reading of ageing through the prism of energy in a range of workshops. The seminar aims to produce a full submission of articles for a special issue of the journal “Culture Unbound”.