The focus of our training program is the battleground between microbes and their environment in their struggle for survival. It is insufficient to study microbiology or immunology as isolated systems if one is to understand the organisms as a component of a larger complex biological web. In order to prepare pre- and postdoctoral students for successful careers as independent researchers in the area of human health, it is necessary and important to give microbiology and immunology students a solid and wide-ranging foundation of knowledge on this theme. In recent years, the development of sophisticated techniques in all scientific arenas now permits the study of microbe/host interactions at multiple levels. Hence, our training program emphasizes an interdisciplinary approach to microbial pathogenesis. The goal of our program is to train PhDs, MD/PhDs, and postdoctoral fellows to be practically and/or theoretically conversant with the latest techniques and experimental concepts in protein structure, molecular biology, bacterial genetics, cellular biology, genomics, proteomics, and immunology. The breadth and depth of such knowledge will increase the effectiveness of their thesis research and give the students the flexibility, confidence, and interest to initiate new programs on new biological systems in the future. It will help them read the relevant literature and chose systems intelligently. It will help them establish fruitful collaborations with scientists outside their immediate field and to be able to understand and adequately critique the work of their collaborators. Finally, the multifaceted nature of this training program will allow our students to approach their future research projects from angles, which few others will be capable of doing. Our highly interactive program, in which preceptors and trainees collaborate extensively between laboratories to study problems in microbial pathogenesis, provides an excellent training environment for our graduate students and postdoctoral fellows.