Recently, there have been calls for health geographers to add critical and theoretical debate to 'post-medical' geographies, whilst at the same time informing 'new' public health strategies (Soc. Sci. Med. 50(9)1273; Area 33(4) (2002) 361). In this paper we reflect on how, alongside 'professional epidemiologies', 'citizen epidemiologies' can have credibility in informing public health policy and practice. We do this by drawing on mixed method and participatory research that used a citizens' panel to articulate the health and social outcomes of the 2001 foot and mouth disease disaster. We consider the difficulties of creating dialogue between on the one hand, time-limited, discrete, theoretical, visible and by implication legitimate, 'professional' knowledge and on the other, ongoing, holistic, experiential and often hidden 'citizen' knowledge of the foot and mouth disease epidemic. Despite significant evidence that in disaster and crisis situations, people need to be actively involved in key 'recovery' decisions (see for example At Risk Natural Hazards, People's Vulnerability, and Disasters, Routledge, London; A New Species of Trouble, Norton, New York), lay accounts, which may in themselves provide valuable evidence about the impact of the disaster, are often ignored. If health geographers are to critically inform 'new' public health policy then we need to consider research approaches that give voice to citizens' understanding of health outcomes as well as those of professionals. If 'new' public health is concerned with the material character of health inequalities, with fostering 'healthy' living and working environments, the promotion of community participation and individual empowerment (Area 33(4) (2002) 361), then we argue that situated, negotiated, everyday geographies of lay epidemiologies can and should inform public health policy.