Last week I ran a small public engagement exercise in the centre of Norwich on the topic of, er... public engagement. The occasion was the annual UEA post graduate research showcase, which involves transplanting around 50 or 60 graduate students from our edge-of-city campus into the heart of Norwich, in the Millennium library. Researchers present their work through a mixture of posters, 'pecha kucha' presentations and cafe conversations. I applied to run a cafe conversation based on my research (on public participation and engagement) partly because I thought it would be fun but also because I hoped it would be an interesting experiment in practising what I preach. Would trying to run a cafe conversation myself alter the way I see the practice of the participation professionals who I study and critique or the way I view engagement exercises more generally? And how would members of the 'public' react to being involved in a conversation about how they could be involved in other conversations about science and science policy decisions? Would this be a reflexive turn too far?