This application represents the third competing renewal for our Training in Emerging Infectious Disease (EID) Training program based at the University of Pennsylvania that supports 2 predoctoral and 2 postdoctoral trainees per year. Of the more than 70 faculty who are affiliated with the Penn microbiology program, a select group of 14 faculty are trainers with this EID T32. All of the trainers have significant EID research programs involving parasites, bacteria, and viruses. An active Executive Committee coupled with an experienced Internal Advisory Committee insures that this program retains a very tight focus on the study of emerging and re-emerging pathogens. As a result, trainers have been dropped from the program when their EID programs have faded while others have been added. This program has served to coalesce EID research training on our campus, with our trainers instituting a popular EID lecture course, a rigorous BSL3 training program, and a Certificate in Public Health Program. We now use Individual Development Plans for our students and postdocs which makes it possible for us to tailor our training activities to best meet the needs of our trainees. Importantly, Penn continues to provide significant, direct support to training activities, including $7 million for our ABSL3/BSL3 and via supporting predoctoral trainees for their first 21 months of graduate school. Thus, our T32 supports trainees only after they have completed all coursework and their prelim exams. Thus far, this T32 has supported 39 trainees, almost all for 2 years each, including 19 Ph.D. students, 4 M.D./Ph.D. students, and 16 Ph.D. postdoctoral fellows. Our 39 trainees have worked in the labs of 18 different trainers. Of the 39 current and past trainees, 20 are women, 19 are men, and 7 are minorities/disadvantaged (18%). Our retention rate is 92%, and those who have completed training and left Penn have obtained good positions (for the postdocs) and excellent postdoctoral positions at leading institutions, with most continuing to study emerging infectious agents. The accomplishments of our trainees coupled with their career progress since leaving Penn shows that our T32 program is indeed training promising young scientists to enter careers in EIDs.