The research of public understanding is gaining a new momentum internationally. In the seminar I will briefly report on a two-day international workshop that took place at the Royal Society in November 2007 which made a bid to define a new agenda for PUS research: mapping the societal conversation of science. This is both a problem of historical development and international comparison, and different data streams. One of the new issues is to address the question of public knowledge and attitudes not only in the context of current controversies, though this might motivate asking questions in the first place, but in the context of historical changes. In other words we need to take stock and have another look at existing databases. For example, Eurobarometer has asked questions pertaining to public sentiments regarding science and technology since the 1970s. A series of eight related EB surveys have recently been integrated (sample size over 60,000; 60 variables), which constitutes a single ‘longitudinal database’ to study the dynamics of the culture of science across EU-12 since the late 1970s. One of the key problems of such analyses will be to disentangle the effects of significant time events, of generation groups and of simply growing older (the problems of cohort analysis) on knowledge and attitudes. We might discuss the conduct and uses of such analyses.