This training program is designed to develop a cadre of young biostatistical scientists to become leaders in integrative and team approaches to understanding biological science in the public health arena. Susceptibility to many complex diseases can be governed by the interactions between modifier genes and environmental factors. In the post-genomic era we are beginning to comprehend and compile the breadth of genetic variation within the human population. Refined use of this information requires the development of advanced methods of biostatistical analyses. In addition, to make significant progress in disease prevention, a hallmark of public health, there is a pressing need to translate advances in basic science into programs and policies focused on preventing common and costly chronic diseases. Only by integrating emerging scientific information into the design of clinical and public health interventions can we fully extract the value of these advances for public health. The established tools of probability and statistical inference remain critical to the success in the training of this new generation of biostatisticians, but in addition they must be conversant with the biological basis and data structures encountered in studies that incorporate genetic information, data produced by expression arrays, and that seek to establish connections between data collected in different approaches to the study of biological systems. They will also need a strong grounding in the information sciences preparing them to utilize computationally-intensive methods such as Markov Chain Monte Carlo procedures and semi-parametric models. This training program combines those elements with experiential training in laboratory science and computational biology and directed interdisciplinary research that will prepare graduates to meet this challenge.