The symposium 'Statistical bases for public health decision making: from exploration to modeling' is the sixth in a series of statistical methods symposia sponsored by the Centers for Disease Control and Prevention (CDC) and the Agency for Toxic Substances and Disease Registry (ATSDR) since 1988. Previous symposia were 'Small area statistics in public health', 'Quantitative methods for utilization of multi-source data in public health', 'Statistical methods for evaluation of intervention and prevention strategies', 'Clustering and health events', and 'Statistics in surveillance'. These symposia underscore the importance of statistical and other analytic methods in understanding and preventing disease, injury and other unhealthy conditions. With government downsizing and increasing competition for funds, it has become more important than ever to base public health decisions on solid statistical and quantitative evidence. Proper data analysis and presentation (including modelling, risk-benefit analysis, smoothing techniques and easily understandable graphic presentation of results), as well as properly designed and executed studies and sample surveys, are important facets of providing such statistical bases, which is why these topics were selected as symposium sub-themes. The sixth symposium consisted of a mixture of plenary sessions, parallel sessions, poster sessions, and a short course. Almost 300 participants from six countries and the U.S.A., representing academia, local, state and federal governments, and other health-related organizations, attended and contributed to all these sessions.