International marketing of animals, animal products and food stuffs and the emergence or re-emergence of food poisoning has raised the risk of international transmission of certain infectious agents. Risk analysis, with its three components, assessment, management, and information, constitutes a new approach to state health policies. To guarantee health safety of the human, animal and plant populations, states can prohibit importation or marketing of food products if their decisions are based on open scientific evidence. Risk assessment is a structured open process evaluating available data designed to modelize transmission of the infectious agent integrating the different elements of the food chain from production to consumption. The assessment process involves four phases, The results of risk assessment depend on the pertinence and the quality of the data used for each of these four phases. Data required to implement risk assessment are unfortunately widely dispersed. The food and agriculture industry, official regulatory agencies, consumer watch organizations, and the scientific community all have useful information for risk assessment. The lack of standard methods to collect, process and diffuse data further complicates the problem.